Sintering of prealloyed PM-steels and wear resistant MMC under consideration of gas-solid interaction

考虑气固相互作用的预合金粉末冶金钢和耐磨MMC的烧结

• 批准号: 86463846
• 负责人: Professor Dr.-Ing. Werner Theisen
• 金额: --
• 依托单位: Lehrstuhl Werkstofftechnik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2008
• 资助国家: 德国
• 起止时间: 2007-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/86463846?language=en
• 关键词: Sintering; prealloyed; PM; steels; wear

In the frame of the first funding period of the project Sintering of prealloyed PM-steels and wear resistant MMC under consideration of gas-solid interaction the influence of a nitrogen containing atmosphere on the sintering behavior and the mechanical properties of sintered parts was investigated. The objective was to gain knowledge about fundamental processes of the powder material during gas-solid interaction. This knowledge shall be used to optimize the process and/or the materials. In this context, the processes on the surface and in the bulk of the powder grain of two different cold work tool steels, one hot work tool steel and one CrMn austenitic stainless steel were investigated. One main topic of the second funding period is to complement the obtained results with two new materials, a duplex stainless steel and a powder metallurgically produced metal matrix composite material (PM-MMC). The matrix material for the PM-MMC is the extensively analyzed CrMn austenitic stainless steel. On the one hand, the PM-MMC combines the knowledge about the carbide-rich cold work tool steels and the single phase austenitic steel. On the other hand, nitrogen as alloying element is of great technical relevance in the field of duplex steels. The objective is to clarify the influence of the atmosphere on the processes on the surface (reduction) and in the bulk (phase transformation, phase composition, etc.) of the powder grains.The second main topic is to use the obtained fundamental results of the first funding period for optimization of processes with technical relevance:In the case of the austenitic stainless steel the focus lies on the enhancement of strength and corrosion resistance by realizing an optimal C/N-ratio combined with full densification. For this purpose the processing route (temperature and atmospheric control) shall be optimized regarding densification, bulk nitrogen concentration, and reduction processes.In case of the cold work tool steels sintering under nitrogen containing atmosphere decreases the solidus temperature of the material. This effect can be explained by the transformation of the vanadium-rich carbides to carbonitrides resulting in a release of carbon to the metallic matrix. The ambition is to design a thermal treatment (temperature and atmospheric control) which combines the beneficial effect of an N2 atmosphere while simultaneously optimizing the hardenability of the investigated steels.The research project is aimed to further establish gas-solid interaction for nitrogen alloying in order to optimize mechanical, corrosive, and tribological properties as well as processing parameters of different high alloyed steels.

在考虑气固相互作用的预合金粉末冶金钢和耐磨MMC烧结项目的第一期资助期间，研究了含氮气氛对烧结行为和烧结部件机械性能的影响。目的是了解粉末材料在气固相互作用过程中的基本过程。这些知识应用于优化工艺和/或材料。在此背景下，研究了两种不同冷作工具钢、一种热作工具钢和一种 CrMn 奥氏体不锈钢的表面和粉末颗粒内部的过程。第二期资助的一个主要课题是用两种新材料补充所获得的成果，即双相不锈钢和粉末冶金生产的金属基复合材料（PM-MMC）。 PM-MMC 的基体材料是经过广泛分析的 CrMn 奥氏体不锈钢。一方面，PM-MMC 结合了有关富碳化物冷作工具钢和单相奥氏体钢的知识。另一方面，氮作为合金元素在双相钢领域具有重大的技术相关性。目的是阐明气氛对粉末颗粒表面（还原）和本体（相变、相组成等）过程的影响。第二个主要主题是利用所获得的基本结果第一个资助期用于优化具有技术相关性的工艺：就奥氏体不锈钢而言，重点在于通过实现最佳 C/N 比与完全致密化来提高强度和耐腐蚀性。为此，应在致密化、本体氮浓度和还原过程方面优化加工路线（温度和气氛控制）。如果冷作工具钢在含氮气氛下烧结，则会降低材料的固相线温度。这种效应可以通过富钒碳化物转变为碳氮化物导致碳释放到金属基体中来解释。我们的目标是设计一种热处理（温度和气氛控制），结合氮气气氛的有益效果，同时优化所研究钢的淬透性。该研究项目旨在进一步建立氮合金化的气固相互作用，以便优化不同高合金钢的机械、腐蚀性和摩擦学性能以及加工参数。

项目成果

Influence of Solution Nitriding of Supersolidus–Sintered Cold Work Tool Steels on their Hardenability

固溶氮化超固相线烧结冷作工具钢对其淬透性的影响

• DOI: 10.3139/105.110234
• 发表时间: 2014
• 期刊: HTM Journal of Heat Treatment and Materials
• 作者: M. Blüm;J. Conrads;S. Weber;W. Theisen
• 通讯作者: W. Theisen

Influence of the PM-Processing Route and Nitrogen Content on the Properties of Ni-Free Austenitic Stainless Steel

• DOI: 10.1007/s11661-014-2701-7
• 发表时间: 2015-03-01
• 期刊: METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
• 影响因子: 2.8
• 作者: Lefor, Kathrin;Walter, M.;Theisen, W.
• 通讯作者: Theisen, W.

Critical investigation of high temperature gas nitriding of a PM tool steel

粉末冶金工具钢高温气体渗氮的关键研究

• DOI: 10.3139/146.110447
• 发表时间: 2011
• 期刊: International Journal of Materials Research
• 影响因子: 0.8
• 作者: S. Weber;W. Theisen
• 通讯作者: W. Theisen