热等静压TiC/H13钢基复合材料的力学性能与合理初始粒径比

Mechanical properties and reasonable initial particle-radius-ratio of TiC/H13-steel composite prepared by hot isostatic pressing

以H13钢粉和TiC粉末为原料,采用热等静压法制备H13钢和TiC/H13钢基复合材料,重点考察TiC粉末与H13钢粉末的初始粒径比（r/R）对复合材料的致密度、宏观硬度、微观组织及拉伸性能的影响。结果表明：直接用市售的H13钢粉和TiC粉制备的TiC/H13钢基复合材料,其致密度和抗拉强度均比H13钢的低,分别为88.2%和544.5 MPa,硬度HRC为62.5,比H13钢的略高。通过构建简单几何关系模型及分析,推导出增强相TiC颗粒与H13钢粉的初始粒径比r/R的合理判据,

TiC/H13-steel matrix composite was prepared by hot isostatic pressing（HIP） H13 and TiC powders, and the effect of the initial particle-radius-ratio（r/R） of H13 and TiC powders on the density, hardness, microstructure, and tensile strength of the composite was investigated. The results show that an unreasonable partial-radius-ratio can lead to a serious reduction in the density and the tensile strength（only 88.2% and 544.5 MPa respectively）, with negligible impact on the hardness HRC（62.5）. A simple geometry-based analytical model was proposed to deduce the reasonable criterion for initial particle-radius-ratio（0.1〈r/R〈0.15）, and the corresponding density range is 0.925-0.943. By refining the H13 powder to meet the reasonable particle-radius-ratio criterion, the density, tensile strength, and hardness of the composite（prepared under the same HIP parameters） increase to 95.3%, 832.3 MPa, and 65 HRC, respectively, with a homogeneous distribution of TiC particles in matrix. The proposed criterion for initial particle-radius-ratio can be useful for guiding and assessing the HIP processing design.