摘要
研究了固溶后冷却速度对CHS-104合金显微组织和高温力学性能的影响。结果表明,合金铸态组织由γ基体、γ'相、γ/γ'共晶相和碳化物组成,碳化物为MC型,主要元素为Ti、Nb、W。固溶处理后,合金析出的γ'相近似球形。其中,空冷时的尺寸为0.1～0.3μm,而炉冷后则增大至0.2～0.8μm。两种冷速固溶后Al、Cr、Mo、Nb元素在枝晶杆和枝晶间的偏析程度减弱,偏析比趋于1。合金力学性能测试结果表明,固溶后炉冷较空冷时的900℃抗拉强度降低,由552MPa降到526MPa,但塑性显著提高,伸长率从9.9%增至21.7%,提高了119%;900℃、200MPa条件下的持久寿命由89.2h降到83.2h。合金拉伸/持久断裂以沿晶/穿晶复合方式呈现。
The influences of solution cooling rate on the microstructure and high temperature mechanical properties of CHS-104 alloy were investigated. The results show that the as-cast microstructure is composed of γ,γ＇ phase,γ/γ＇ eutectic and （Ti, Nb, W）C with type of MC. After heat treatment, a large amount of spherical shape γ＇ phase precipitates in the γ matrix. The size of γ＇ phase range is 0.1-0.3 μm and 0.2-0.8 μm after air cooling and furnace cooling respectively. The microsegregation of AL, Cr, Mo, Nb decreases distinctly. Compared to those air cooling counterpart, the tensile strength at 900℃ decreases after furnace cooling, the lasting life at 900℃ × 200 MPa also reduces from 89.2 h to 83.2 h, while the elongation increases 119% from 9.9% to 21.7%, which means that the plastic property is improved dramatically. Meanwhile, the type of fracture is a mixture of transcrystalline and intergranular ductile fracture.
出处
《热加工工艺》
CSCD
北大核心
2013年第10期216-219,171,共5页
Hot Working Technology
