Enhanced mechanical properties and thermal stability of hot-rolled Mo-0.5%ZrC alloy
Enhanced mechanical properties and thermal stability of hot-rolled Mo-0.5%ZrC alloy
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DOI：
10.1016/j.msea.2022.143803
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发表时间：
2022-08-26
期刊：
影响因子：
6.4
通讯作者：
Wang, X. P.
中科院分区：
文献类型：
--
作者：
Jing, K.;Cheng, X.;Wang, X. P.
采用粉末冶金和热轧工艺制备了力学性能和热稳定性均得到提高的Mo-0.5wt%ZrC合金板材。轧制态Mo-0.5%ZrC板材的室温抗拉强度（UTS）为725 MPa，延伸率（TE）为24.1%。Mo-0.5%ZrC合金经1300 ℃退火后，抗拉强度降低到676 MPa，变形抗力提高到32.8%。Mo-0.5%ZrC合金经1600 ℃退火后，抗拉强度为507 MPa，变形抗力显著提高到56.4%。此外，Mo-0.5%ZrC合金表现出约1300 ℃的高再结晶起始温度。纳米ZrC颗粒的加入可以通过钉扎位错和晶界来提高强度和高温稳定性。同时，ZrC纳米颗粒还可以与杂质氧反应生成Zr-C-O或ZrO 2颗粒，从而缓解Mo合金的氧脆。但是，氧化物颗粒在高温下易于长大，导致分散体的数密度降低，分散强化效果降低。
Mo-0.5 wt%ZrC alloy plate with enhanced mechanical properties and thermal stability was manufactured by powder metallurgy and hot rolling. The as-rolled Mo-0.5%ZrC plate shows an ultimate tensile strength (UTS) of 725 MPa and a total elongation (TE) of 24.1% at room temperature. After annealing at 1300 C, the UTS of Mo-0.5%ZrC alloy decreased to 676 MPa while the TE increased to 32.8%. After 1600 C annealing, the UTS of Mo-0.5%ZrC alloy is 507 MPa and the TE increased significantly to 56.4%. Additionally, Mo-0.5%ZrC alloy exhibits a high recrystallization start temperature of about 1300 C. The addition of nanoscale ZrC particles can enhance the strength and high temperature stability by pining dislocations and grain boundaries. Meanwhile, ZrC nanoparticles can also react with the impurity oxygen to form Zr-C-O or ZrO2 particles, and thus alleviate the oxygen embrittlement of Mo alloy. However, the oxide particles tend to grow into larger particles at high temperatures, leading to decreased number density of dispersoids and lower dispersion-strengthening effect.