论文部分内容阅读
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 effect of solid solution cooling rate on the microstructure and mechanical properties of CHS-104 alloy was investigated. The results show that the as - cast alloy consists of γ matrix, γ ’phase, γ / γ’ eutectic phase and carbide. The carbide is MC type and the main elements are Ti, Nb and W. After solution treatment, the γ ’phase precipitated by the alloy is nearly spherical. Among them, the size of air-cooled 0.1 ~ 0.3μm, and furnace cooling is increased to 0.2 ~ 0.8μm. The segregation degree of Al, Cr, Mo, Nb between the dendrite rod and dendrite decreased after the two kinds of cold solid solution treatment, and the segregation ratio tended to one. The mechanical properties of the alloy showed that the tensile strength at 900 ℃ decreased from 552MPa to 526MPa, but the ductility increased significantly from 9.9% to 21.7%, an increase of 119%. The life expectancy at 900 ℃ and 200MPa decreased from 89.2h to 83.2h. Tensile / permanent fracture of the alloy is presented as a crystalline / transcrystalline composite.