【摘要】 本文探讨了WC-15wt%Co硬质合金的力学性能与热处理工艺的关系。并以X射线衍射和透射电子显微镜为主要手段,研究了合金在烧结后的冷却或淬火中粘结相由面心立方β—Co→密排六方α-Co转变的马氏体相变过程。分析了热处理前后WC硬质相的表层宏观应力及其对合金性能的影响。比较了合金在热处理态和常规烧结态下显微结构的差异。结果表明,粘结相面心立方β-Co含量的升高;WC相表层宏观压应力的增加以及WC晶粒间邻接度的减少是该合金热处理的主要强化机理。更多还原

【Abstract】 This paper described the relation of mechanical properties to the heat-treatment process of WC-15Wt% Co cemented carbide. The martensitic transformation of β-Co(fcc)→α-Co (hcp) were studied in binder phase of the alloy during the conventional sintering and heat treatment by means of XRD and TEM. and the macrostresses were analyzed on surface layers of WC phase in the specimens with and without heat treatment, and on their influence on the mechanical properties of the alloy. Observations of microstructures of both heat-treated and conventional sintering specimens showed that increases in the concentration of β-Co(fcc) in binder phase and in the compression stresses. and the reduced contiguity of WC grains are responsible for the heat-treatment hardening of WC-Co cemented carbides.更多还原