Laser powder bed fusion (LPBF) is an advanced manufacturing process capable of additively fabricating injection mould inserts with complex internal conformal cooling channels (CCC) in various tool steels. The recent successful development of a hybrid-build hybrid-metal LPBF technique enables this metal additive manufacturing (AM) technology to be a superior and economical alternative to the...
The present work focuses on the knowledge-based expert system to develop an automated die and punch tools design for the sheet metal forming process (deep drawing operation). The major limitation of the conventional forming process is the manufacturing of dies. As the attributes of the final component varies, the configuration of the tooling (punch and die) require to be modified. Hence, the...
Low Pressure Die Casting (LPDC) is a widely used process for producing automotive components. Those components have high mechanical requirements, which are difficult to achieve reproducible within standard LPDC process conditions. Due to those high requirements, process instabilities and casting defects, the scrap rates are sometimes very high, reaching values of 20%. To ensure part...
Abstract
Additive manufacturing methods are applied in various fields of industry because of advantages like rapid production of parts or freedom in design. In most cases materials with a low amount of carbon, e.g. stainless steels, are used for 3D-printing. An important and widely used representative of these grades is the material 1.4404 (316L), which is well established because of an easy...
The public funded project AddSteel aims to develop functionally adapted steel materials for additive manufacturing. Based on the AM process laser powder bed fusion (LPBF) the holistic process chain, including alloy design, powder atomization, additive manufacturing and post heat treatment is considered to achieve this objective.
Tool steels are usually characterized by higher carbon content...
Wire is all around us and it forms joints in our structures, stabilizes our tires and transports electricity. In almost every complex product there are components made from wire. In wire drawing hot rolled material is drawn through a single or a series of tools called drawing dies, reducing the cross-section and enhancing the mechanical properties of the material. The tribological conditions...
The need to develop products with superior performance has led to the development of new materials and heat treatments. In the case of tools, well designed and controlled heat treatment is crucial to achieve appropriate combination of superior properties. In the huge number of heat treatment and surface engineering techniques, deep cryogenic treatment (DCT) shows very promising results....
High pressure die casting (HPDC) is a well established manufactory process which allows, specially the automotive sector, to make high precision components in fast paced rates. Furthermore, the increasing need for lighter components stimulate the use of low density alloys, making the HPDC suitable for this emerging demand. Nevertheless, every manufacturing process has spaces for improvement....
The objective of this work is to verify the machining process behavior of the Cr3C2 25NiCr HVOF coating. which can be used for the automotive, aerospace industries and naval, improving the sufarce finish of the thermal spray. The coating is machined with a 12mm diameter carbide ball nose tool, in which the tool is parallel to the surface, with a cutting speed of 100m/min, and a feed of...
As most steelmakers, Erasteel is fully involved in decreasing its CO2 and environmental footprint. Erasteel already produces its high-speed steel using 90% recycled material and has the ambition to reach 100% in near future. The today’s remaining 10% are mainly metallic oxides (V2O5, MoO3) or ferro-alloys (FeW, FeCr, FeSi) and cobalt (Co). The total life assessment shows that producing from...
Laser Metal Deposition (LMD) is one of the promising processes for additive manufacturing thanks to its ability to produce practically large metallic parts and complex geometries in a cost-effective manner and short lead time. Moreover, it can be utilized for reparation and cladding, making it an outstanding choice for tooling and molding. In the current work, the heat treatment behavior of...
The constantly increasing requirements for tool materials continuously set new challenges concerning loading capacity, resistance to damage and crack propagation as well as the characterisation of these properties, especially at elevated temperatures that arise e.g. at cutting edges when cutting metal workpieces. Essential progress in the field of tool technology and knowledge-based selection...
Thanks to its high hardness and cracking resistance in hot-working operations, AISI H13 is acknowledged as all-around steel for die making in high-pressure die casting, extrusion, and hot stamping. In addition, the opportunities offered by Additive Manufacturing (AM) to fabricate complex shapes and closed channels strongly meet the needs of hot-work tools designers but typically are not easily...
Chromium- and chromium-vanadium ledeburitic tool steels are extensively used in industry, for cold work tooling. The applications where abrasive wear is dominant such as fine-blanking, punching, cropping, shearing or trimming are typical examples. For these applications the steels must have high strength and hardness. On the other hand the tools have to withstand the chipping or cracking in...
It has long been recognized that die surface roughness and lay have significant effects on flow behavior in sheet metal forming processes. In comparison, relatively little research has been conducted to explore similar effects in bulk forming processes. In the present paper, an experimental study was conducted using warm and hot working conditions to investigate how directional (anisotropic)...
Copper-Beryllium precipitation hardening alloys are widely used to manufacture molds in plastic injection moulding due to the excellent thermal properties combined with good mechanical strength and corrosion resistance. However, the lower hardness and wear resistance compared to tool steel, as well as the higher cost, limited their wider use. A tool steel cladding on copper alloy substrate...
The purpose of this study is to assess the impact of different combinations of cryogenic treatments and tempering regimes on tribological properties of Cr-V tool steel against a CuSn6 counterpart. Dry sliding wear experiments were performed using a pin-on-disk tribometer according to the Taguchi method. Tribological behaviour is investigated under four process parameters at mixed levels:...
Powder metallurgy (PM) high speed steels have traditionally been used for tools but are gaining increased usage for demanding components such as rings in bearings and fuel injection. These components, but also many of the tools, are under cyclic load, sometimes several millions of cycles. For that reason, the fatigue resistance of PM-HSS (HSS) is one of the most important mechanical...
Near full-dense and crack-free AISI H13 hot work tool steel was fabricated using laser-directed energy deposition (L-DED). Two different heat treatment schedules, i.e., direct tempering of the as-built part (DT) and austenitization and quenching prior to tempering (QT), were selected. The effect of heat treatment on the microstructure, hardness, fracture toughness (Kapp), and softening...
Electro-slag remelting is an important process to produce high quality tool steels. Thereby the slag composition has a strong effect on the remelting behavior in general and on the electric energy consumption as well as on the removal of non-metallic inclusion. Later aspect is strongly related to chemical reactions taking place between the slag and the metal and thereby determines the...
In hot metal forming processes, the temperature of the forming tool is increased under repeated use during mass production conditions. Two-phase water-based lubricants may be applied to cool down the forming tool, in which the liquid agent would evaporate or decompose rapidly with dry matter deposited on the tooling surface during the dwelling time before the forming process commences. In this...
It is known that carbide size, height and orientation are very effective on wear properties such as galling and abrasive wear. Carbides can also act as stress points for crack initiation. Therefore, different carbide morphologies of Cr-Mo-V powder metallurgical tool steels with the similar composition were compared within the scope of this work.
In our study, larger carbides produced via...
Intelligent material combinations for the production of multi-material systems as well as lightweight construction to save weight are becoming increasingly important in industrial applications. But the joining process of dissimilar materials, such as high-strength steel and aluminium as well as steel and continuous fiber-reinforced plastics (CFRT), which are often used in multi-material...
The failure of die-casting molds is often caused by the the thermo-mechanical fatigue (TMF) damage because of oxidation-fatigue-creep complicated interactions. Due to the complexity and difficulty of TMF experiment, the description of damage and failure process of the material in the TMF process has been lacking at present. In this paper, the TMF behavior of AISI H13 steel under common...
Although anisotropic surface textures have been used to improve tribological performance in various mechanical systems in recent years, relatively few researchers have investigated the use of such textures in metal forming processes. In addition to achieving a better understanding of how anisotropic surfaces influence forming behaviour, it must also be considered that directional friction...
Due to the increase of the complexity of the products and the shorter time-to-market, it is also necessary to develop the required tooling to attend to the planned deadlines. This scenario requires advancing the state-of-the-art frontier to improve the tooling competitiveness and productivity.
To achieve such improvement and increase in competitiveness, it is necessary to insert the tooling...
Wear and in particular abrasive wear in injection molding is a core research topic for the institute of injection molding of polymers at Montanuniversität Leoben. The standard application-oriented test for abrasive wear of polymers on plastic mold steels is the platelet-wear-tester method in which two steel specimens form a thin wear slit. The glass fiber reinforced polymer melt is injected...
Intelligent temperature control of die casting moulds opens up enormous potential for improving cycle times, tool life, as well as the structure and warpage of the cast parts. In this context, “intelligent temperature control systems” are three-dimensional, contour-adapted temperature control systems that can be produced using generic AM processes. Moving them close to the component and...
Usually, tool steels are used in quenched and tempered condition. Due to the phase transition from austenite to martensite and the volume change during the transformation, controlling of distortion might be a challenge. The end user’s demand for high hardness of the final tool leads to a poor machinability.
Engineering steels with bainitic structure are generally based on a low alloying...
Additive manufacturing (AM) has become of major interest in the tooling industry because of its opportunity to manufacture parts of complex shape or with internal structures such as cooling channels. Nevertheless, the application of AM-processes for the manufacturing of tools is often discarded because processable materials that are suitable for the high demands on strength, wear resistance...
Laser additive manufacturing enables the one-step fabrication of complex parts. This technology has been applied for the tooling with the advantages such as fast tool development, low material cost and high geometry freedom. However, pores and carbides network, which are not avoidable from the LPBF process, deteriorate the fatigue strength significantly. Hot isostatic pressing (HIP) with...
The process of quality is traditionally considered non-productive. That is why the manufacturing industries aim to decrease inspection times to a bare minimum without sacrificing quality. With recent developments in Industry 4.0 technologies, data-driven in-situ quality control is a factor industry is increasingly relying on to minimize inspection times. Surface roughness parameter prediction...
Additive Manufacturing (AM) is becoming more common as manufacturing technique and the obvious benefits of freedom of design and production speed can clearly be utilized in the manufacturing of tools and molds. One of the most important criteria in producing molds for plastic injection is service life. This paper evaluates a mold produced using the conventional machining method versus mold...
The industry segment of tooling applications has demonstrated significant developments in the field of Additive Manufacturing (AM) in the last decade. Progressing all the way from prototyping to high Technology Readiness Levels (TRL), thus enabling production capabilities. Especially, in relationship to Laser Powder Bed Fusion (L-PBF) and Laser Metal Deposition (LMD) technologies. The latest...
The stress immersion corrosion of 4Cr16Mo/4Cr16MoCu materials was studied to explore the effect of Cu on the corrosion resistance of 4Cr16Mo series materials. Under the same quenching and temperature, 4Cr16MoCu material has better stress corrosion resistance than the other Cu free material. Both materials will crack after soaking under stress, the greater the stress, the greater the risk of...
In the surface-critical stands in hot rolling mills, so-called indefinite-chill alloys are used as shell materials for the work rolls. The microstructure of these materials consists of cementite, graphite as well as different other carbides which are embedded in a martensitic/bainitic matrix. In the past ten years, indefinite-chill materials were intensively developed to meet the higher...
Abstract
The addition of copper and sulfur can improve the cutting performance of the pre-hardened plastic mold steel, and the effect of improving the cutting performance is similar, and both have the effect of wrapping lubrication and reducing friction. The four types of P20 plastic mold steels were adjusted to the same hardness level through the heat treatment process, and the...
From the viewpoints of the microstructure and phase, the friction and wear properties under different friction pair conditions, different wear loads and lubrication methods, the SLD-MAGIC, SKD11 and DC53 cold-working die steels were systematically estimated, which provided theoretical support for reasonable material selection of cold-working dies. The results show that all three steels contain...
The powder metallurgical incorporation of hard phases in steel matrices is an established concept to form a metal matrix composite with excellent mechanical properties. Especially TiC has been extensively used in a wide variety of steel matrices in the past. This is primarily due to its high hardness and decent bonding behavior towards steel matrices. While the stability of TiC particles is...
Heat treatment is an essential tool to adjust the desired properties of steels. The typical heat treatment of martensitic stainless steels consists of hardening and subsequent tempering once or several times. During tempering the common tempering mechanisms occur, such as carbide precipitation, relaxation of the fresh martensite, destabilisation of the retained austenite and subsequent...
Electron beam powder bed fusion (E-PBF) is a promising additive manufacturing method efficiently used for materials susceptible to thermal cracks, like high-alloy cold work tool steels. The method provides high build chamber temperature, pre-heating of the build and slow cooling reducing thermal stresses during manufacturing. In this investigation, wear performance of conventional and E-PBF...
In cold work applications, tool steels with high carbide contents are mainly used as cutting and stamping tools. The efficiency of cold forming processes depends on the tool life, which is limited by wear resistance and fatigue strength. Forming tools often fail due to fatigue fracture since fatigue design is usually not performed. Microstructural and statistical understanding of the...
Improving tool life under cyclic loadings is of great economic interest, since forming tools often fail due to fatigue fracture initiated at volume or surface defects. Increasing the fatigue strength of tool steels can be achieved through improved steel making or properly chosen case hardening. Diffusion layer plasma-nitriding has never been investigated statistically or...
Global demands, like a reduction in carbon dioxide emissions and increased functional integration, require efficient forming operations and innovative process combinations in the manufacturing industry. One promising approach is the application of bulk forming operations on sheet metal in order to merge the advantages of both classes, defined as sheet-bulk metal forming. In this context, the...
Hot stamping tools require cooling channels, preferably with a variety of sizes and a high positioning flexibility. Conventionally, these are machined. This represents a disadvantage because of the limited accessibility for milling tools and the low flexibility. By means of the Directed Energy Deposition (DED) process a flexible design of the cooling channels is possible. For this,...
For industrial mechanical processing of food like cutting, slicing, grating, passing or similar applications, tools of martensitic stainless steels are preferably used because of their high hardness and corrosion resistance. The latter is decisive to avoid contamination of foodstuff by elements transferred from the steel alloy into the processed food.?In this work various martensitic stainless...
Abstract: During metal cutting, the employed cutting tool experiences thermo-mechanical loads that causes wear at the interacting surfaces, hence, limiting the tool life. The speed of cutting and active feed of tool dominates the wear magnitude; hence, these factors were considered in the developed analytical tool wear model. Considering the high heat generation and consequent temperature...
The workpieces in toolmaking are becoming increasingly complex and individualized. This complexity is transferred to the manufacturing process chains required for production. Thus, the cross-technology design of process chains is crucial in reducing costs and lead times while improving quality. The tool making industry applying a wide range of heterogeneous technologies further complicates...
Tool steels are generally produced through a variety of manufacturing routes including conventional route, electro-slag remelting (ESR) and/or vacuum arc remelting (VAR), and powder metallurgy (PM). The PM route offers various advantages for certain steel grades such as advanced alloy composition, homogeneity, and well-defined hard phase particle size distribution. A study on a martensitic...
The use of Laser Additive Manufacturing (LAM) techniques, such as Laser powder bed fusion (L-PBF) or Laser Directed Energy Deposition (L-DED) for the manufacturing of forming tools has gained increasing interest in both industry and academia due to the processes’ high geometrical flexibility. LAM allows for a layer-wise build-up of parts based on 3D-CAD-data by either the local melting of a...
Martensitic precipitation hardening stainless steels are used as tooling material especially for injection molding of corrosive plastics due to their excellent corrosion resistance and good mechanical properties. The additive manufacturing of tools is gaining attention in tool repair, and it has the potential to be used for tool production. The investigation of laser metal deposited...
Abstract
The improvement of material properties for tool applications has always been an overriding development topic. To minimize wear, tool steels, special alloys based on nickel or cobalt and metal matrix composites (MMC) has been developed – either as molten or as powder metallurgical materials. In this study a new kind of material is described which combines the outstanding properties of...
The development of martensitic steels suitable for exposure to corrosion with simultaneous wear attack is a challenging task, as corrosion and wear resistance are opposite properties in terms of alloying. With the development of NbC-containing corrosion-resistant steels, it has been possible to combine these properties. Due to its higher hardness, NbC increases the wear resistance of the steel...
Meeting increasing requirements concerning part quality and process profitability despite difficult-to-machine materials is only possible with a deep process understanding. In this context, knowledge about the process temperature is of decisive im-portance, since it affects material properties such as hardness or forming behavior as well as chemical and physical interac-tions between tool,...
Today's tool and die making industry is characterized by increased individualization and complex manufacturing processes. Therefore, toolmaking companies are forced to always push the limits of what is technically feasible. The usual heterogeneous use of different manufacturing technologies generates high manual planning efforts and requires a cross-technology process understanding. A large...
Böhler W360 ISOBLOC is well known as high performance hot work tool steel. The main characteristics are high thermal and wear stability, hardness in use up to 57 HRC and particularly the resistance against crack propagation. Therefore the main applications are as thermal and mechanical highly stressed tools among others for Al high pressure die casting (HPDC) inserts.
Nowadays the...
Die casting tools with improved cooling by conformal cooling produced using additive manufacturing allow to reduce cycle times and improve the part quality. Most available tooling materials for additive manufacturing are however, either not enough heat resistant or difficult to print. The paper presents Pearl®Micro TS700, an innovative 5% chromium, precipitation hardening tool steel, with a...
The die-casting molds employed with molten aluminum under high pressures are subjected to severe localized corrosion, which is due, mainly, to the intense thermal cycling at temperatures around 700 °C. The recovery of molds usually involve the removal of the damaged region and reconstruction through welding. By a different approach, the resistance and lifespan of the recovered piece can be...
Stainless austenitic steels like the 316L are very popular in the field of Additive Manufacturing. This clearly is due to the easy processability of austenitc steels in the AM process. Austentic steels can be printed with little distortion, which means that less support structures are required. This again reduces cost-intensive build-time as well as post-processing requirements. One...
To predict the solidification and the product properties of complex alloyed tool steels, a deep understanding of the transformation behaviour during and after solidification, depending on the chemical composition, is a key competence. The knowledge of primary carbide formation plays an essential role in higher-alloy tool steels, where many different carbide types (e.g. M7C3, M23C6, M6C und MC)...
Extruder screws, as applied for example in plastics compounding or food industries, often require both wear and corrosion resistance. Therefore, the production process of these screws is divided up into shaping of geometry on the one hand and wear protection together with surface fine processing on the other hand. Recently developed FeCrMnCN stainless austenitic high interstitial steels (HIS)...
Functionally Graded Materials (FGM) represent an interesting innovation, compared to bulk materials, as they allow a continuous properties variation in components undergoing complex solicitations in service. Laser Additive Manufacturing by Direct Laser Metal Deposition (DLMD) is one of the most important processes to manufacture FGMs. It is based on a material in the form of powder or wire...
Mechanical wear is responsible for obsolescence of mechanical parts due its geometrical changes. Tooling is directed affected by wear and its generated costs have a huge impact over manufacturing final prices. Manufactory processes like high pressure die casting (HPDC) lies on the die geometry to acquire the requested dimensional precision and surface quality. A usual way for overcoming wear...
The service life of die is closely related to its service performance. The service performance requirements of die steel materials are increasing. High quality, high efficiency, long life, and low failure are the general trend of the development of modern high-end mold equipment. The service temperature of hot work die steel can reach 500-700 ℃,and bear large mechanical load at the same time,...
The thermal stability and impact toughness of SDHA steel at different temperatures were investigated by hardness measurements and Charpy impact tests. After solid solution, undissolved VC carbides were found in SDHA steel. Besides, when solid solution temperature surpassed 1200 °C, the austenite grains began to grow. The carbide type of SDHA was VC carbide by solid solution and aging....
Laser Powder Bed Fusion (LPBF) is an additive manufacturing process that enables the production of complex shaped components. Conventional high-carbon tool steels tend to cracking and warping during LPBF due to internal stresses caused by the rapid solidification. Expensive atomization and long lead times for powder generate high costs for material development in this processing route.
The...
Retained austenite is widely regarded as a detrimental microstructural constituent in high-alloyed tool steels. However, an undesired amount of it often remains in the microstructure due to the incomplete transformation of austenite into martensite during the hardening process of tool and high-speed steels. Resulting effects are dimensional instabilities and internal stresses after the heat...
High-quality tool steels are the backbone of our production system across the globe: they shape a wealth of other materials to our convenience, producing parts of all sizes and geometries. Typical properties of these tools are high strength, hardness, wear resistance, coupled with sufficient toughness. These properties are achieved in tool steels by a multiphase microstructure, which can be...
ROTA 2030 (in English, Route 2030) is a Brazilian strategic program for developing the automotive sector. Among its priority lines, it focuses on bringing competitiveness to the Brazilian tooling industrial sector. Called “Ferramentarias Brasileiras Mais Competitivas” (in English “More Competitive Brazilian Tool Shops”), it is a line organized in four axes, among which the first three...
Steels for production of frames for plastic molds frequently need to be stainless, while at the same time require large amounts of machining. Machinability as a crucial property can be enhanced by the addition of sulfur, resulting in the formation of favorable sulfides, which in turn can deteriorate mechanical properties and resistance to corrosion. The detrimental effect on mechanical...
The corrosion behavior of hot stamping tool steel was studied by alternate immersion method. The results show that the corrosion mode was comprehensive corrosion, the applied stress level affects the corrosion, the corrosion rate increased with the increase of stress, the corrosion resistance of high hardness (54HRC) materials was lower than that of low hardness (50HRC), and this phenomenon is...
Wire drawing is one of the oldest and most used metal forming processes. In a conventional wire drawing process, the cross-section of the wire is reduced to the final dimension by drawing the wire through a series of drawing dies made of cemented carbide or poly crystalline diamond. Despite the use of different types of lubricants wear of the dies, frequently resulting in time-consuming die...
Undeniably, reliable and accurate data is necessary in industry 4.0 revolution. This data is generated from sensors placed in the casting process. Therefore, sensor implementation strategy must be thoughtfully designed. In other words, how to put a sensor closer to the relevant phenomena that needs to be controlled and how to assure sensor’s life and tool performance in doing so.
Mold...
Corrosion-resistant mould steels are used to process chemically aggressive plastics such as PVC or PET in many plastic moulding processes such as extrusion, injection, blow and compression moulding. Free machining (sulfurized) grades are common choice for holders where the requirements are machinability and dimensional stability, whereas low sulfur grades are preferred for high surface finish...
Direct Laser Metal Deposition (DLMD) is an additive manufacturing technique getting growing attention thanks to the possibility to produce very complex parts in short time and in a cost-effective manner. Possible applications of this technology are tools with conformal cooling channels and claddings for dies and moulds reparation. AISI H13 is a hot work tool steel, typically used for hot...
Longer tool life and shorter cycle times in production are particularly relevant for die casting and injection moulding to ensure the economic efficiency of these manufacturing processes. The demands on tool steels are constantly increasing. Thermodur 2383 Supercool is a novel tool steel that combines excellent mechanical properties and high hot wear resistance with outstanding thermal...
The growing importance of lightweight construction to reduce resource consumption is leading to the increased use of multi-material systems consisting of components with varying geometric and mechanical properties. However, the joining processes to manufacture these assemblies are gradually reaching their limits, which is why innovative processes and methods are required. To enhance the...
Multiple cycles of tool dimensional correction during tryout process are one of the most critical aspects in manufacturing of stamping tools, causing significant impact to its production cost. An alternative to reduce tryout time and cost is to perform the dimensional corrections in a virtual model, so that ideally, all the corrections can be done to the simulation before the test of the...
The speech will also focus on the production of Metal Powders and Powder Metallurgical Steels and especially its associated production technologies like HIP, MIM and AM. As they are and will become key future core technologies for a number of demanding products and thus for the usage in different associated industries. The presentation will also highlight the actual supply and demand situation...
