Scholarlink

<p>Powder metallurgy processes are widespread in different industry sectors as they allow flexible selection of the composition and operating properties of the manufactured products. In this paper, an insight into the key mechanical, structural and operational properties of newly designed Fe-Gr-Br metal matrix composites (MMCs) after thermo-mechanical processing (TMP) is described. The structure of the MMCs studied consists of areas of steel matrix with a pearlite structure with a small amount of cementite and areas of copper-based phase located along the grain boundaries of the matrix. During the infiltration process, molybdenum disulfide breaks down into molybdenum trisulfide Mo<sub>2</sub>S<sub>3</sub> and free sulfur. Increasing the strain degree leads to increasing refinement of the MMC steel skeleton structure and its texturization. The use of TMP increases the hardness of the material by up to 40&#xa0;pct. The flexural strength increases in proportion to the strain degree. The use of TMP also leads to changes in the MMC sub-structure. The mean size of the crystalline domains decreased by 10–15&#xa0;pct after 50–70&#xa0;pct straining of MMC. Relative micro-deformations of the crystal lattice depend on the strain degree more significantly and under 70&#xa0;pct straining, they increase 10 times. The dislocation density after TMP can be increased up to 200 times compared to the material in the initial state. When cutting, with an increase in the feed rate, an unambiguous minimization of <i>Sq</i> is observed under 50&#xa0;pct straining of the material. Increasing the feed rate results in the formation of valleys and ridges on the machined surface. Single peaks of different heights are also present on the machined surfaces. At friction joints, the peaks can be sheared off and transformed into the wear products, resulting in accelerated wear of the interacting materials. The analysis of the surface topography details revealed a no. of phenomena specific to the finish turning of the MMCs tested, namely, build-up edge, micro-particles, micro-cracks, and plastic side flow. The occurrence of these phenomena depends on the turning parameters and strain degree and they can seriously reduce the operating life of the products.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

An Insight into the Key Structural, Mechanical, and Operational Properties of Newly Designed Fe-Gr-Br MMCs After Thermo-Mechanical Processing

  • 期刊论文

  • 发表日期：

    2025年4月27日

查看全文
  • Larisa Dyachkova,
  • Eugene Feldshtein,
  • Kamil Leksycki,
  • Grzegorz Krolczyk,
  • Alexandra Zverko

摘要

Powder metallurgy processes are widespread in different industry sectors as they allow flexible selection of the composition and operating properties of the manufactured products. In this paper, an insight into the key mechanical, structural and operational properties of newly designed Fe-Gr-Br metal matrix composites (MMCs) after thermo-mechanical processing (TMP) is described. The structure of the MMCs studied consists of areas of steel matrix with a pearlite structure with a small amount of cementite and areas of copper-based phase located along the grain boundaries of the matrix. During the infiltration process, molybdenum disulfide breaks down into molybdenum trisulfide Mo2S3 and free sulfur. Increasing the strain degree leads to increasing refinement of the MMC steel skeleton structure and its texturization. The use of TMP increases the hardness of the material by up to 40 pct. The flexural strength increases in proportion to the strain degree. The use of TMP also leads to changes in the MMC sub-structure. The mean size of the crystalline domains decreased by 10–15 pct after 50–70 pct straining of MMC. Relative micro-deformations of the crystal lattice depend on the strain degree more significantly and under 70 pct straining, they increase 10 times. The dislocation density after TMP can be increased up to 200 times compared to the material in the initial state. When cutting, with an increase in the feed rate, an unambiguous minimization of Sq is observed under 50 pct straining of the material. Increasing the feed rate results in the formation of valleys and ridges on the machined surface. Single peaks of different heights are also present on the machined surfaces. At friction joints, the peaks can be sheared off and transformed into the wear products, resulting in accelerated wear of the interacting materials. The analysis of the surface topography details revealed a no. of phenomena specific to the finish turning of the MMCs tested, namely, build-up edge, micro-particles, micro-cracks, and plastic side flow. The occurrence of these phenomena depends on the turning parameters and strain degree and they can seriously reduce the operating life of the products.