Abstract In this research, Co–30Cr–6Mo alloys were fabricated by vacuum hot-press sintering technique. The experiments utilized various hot-press sintering temperatures (1100 °C, 1150 °C, 1200 °C and 1250 °C) and hot-press pressures (20, 35 and 50 MPa) to find the optimal parameters for Co–30Cr–6Mo alloys, while simultaneously investigating the differences in microstructural characteristics and properties. The experimental results showed that the optimal hot-press sintering parameters of this sample were 1150 °C at 35 MPa for 1 h. Meanwhile, Co–30Cr–6Mo alloys possessed the optimal mechanical and electrical properties. Among them, the sintering density reached 8.13 ± 0.01 g cm−3, the hardness and TRS increased to 78.9 ± 0.2 HRA and 2672.2 ± 25.8 MPa, respectively, and the electrical conductivity was 3.11 ± 0.95 × 104 S m−1. TEM observation also identified the stacking faults, FCC and HCP structures of the Co phase, and the partial Cr23C6 carbides precipitated in the Co–30Cr–6Mo alloys, respectively. Consequently, the sintering characteristic of Co–30Cr–6Mo was effectively improved, and the mechanical properties were enhanced at a relatively lower sintering temperature by the vacuum hot-press sintering process.

中文翻译：

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真空热压烧结Co-30Cr-6Mo合金显微组织特征和力学性能的原位TEM观察

摘要 本研究采用真空热压烧结技术制备了Co-30Cr-6Mo合金。实验利用各种热压烧结温度（1100 °C、1150 °C、1200 °C 和 1250 °C）和热压压力（20、35 和 50 MPa）来寻找 Co-30Cr-6Mo 的最佳参数合金，同时研究显微结构特征和性能的差异。实验结果表明，该样品的最佳热压烧结参数为 1150 ℃、35 MPa、1 h。同时，Co-30Cr-6Mo 合金具有最佳的机械和电气性能。其中，烧结密度达到8.13±0.01 g cm-3，硬度和TRS分别提高到78.9±0.2 HRA和2672.2±25.8 MPa，电导率为3.11±0.95×104 S m-1。TEM 观察还确定了 Co 相的堆垛层错、FCC 和 HCP 结构，以及在 Co-30Cr-6Mo 合金中析出的部分 Cr23C6 碳化物。因此，通过真空热压烧结工艺，Co-30Cr-6Mo的烧结特性得到有效改善，并且在相对较低的烧结温度下提高了力学性能。