650℃时效HR3C耐热钢的显微组织与高温拉伸性能  

Microstructure and high-temperature tensile properties of HR3C heat- resistant steel after annealing at 650 ℃

作　　者：陈国宏[1] 潘家栋[2] 王家庆[1] 刘俊建[1] 白小龙[2] 张建华[2] 张涛[1] 汤文明[2] 

机构地区：[1]安徽省电力科学研究院,安徽合肥230601 [2]合肥工业大学材料科学与工程学院,安徽合肥230009

出　　处：《材料热处理学报》2014年第2期104-109,共6页Transactions of Materials and Heat Treatment

基　　金：安徽省电力科学研究院技术开发基金(103-413426)

摘　　要：针对650℃直到3000h时效的HR3C钢，研究其显微组织的变化及对其高温拉伸力学性能的影响，探讨650℃时效HR3C钢的高温拉伸断裂机制。结果表明：高温时效过程中，晶界强化、晶内弥散强化和奥氏体基体脱溶弱化等效应导致时效HR3C钢的高温拉伸力学性能发生明显变化。时效初期（〈500h）HR3C钢高温强度变化不大；时效中期（500～1000h）HR3c钢高温强度大幅提高，但塑性持续降低；时效后期（〉1000h），HR3C钢组织结构渐趋稳定，其强度和塑性变化不大。随时效时间延长，HR3C钢高温拉伸断裂机制由正断向剪切断转变。Abstract：Microstructure and high-temperature tensile properties of HR3C steel after annealing at 650 ℃for long-time till 3000 h were studied. High-temperature tensile fracture mechanism of the annealed steel was also investigated. The results show that the high- temperature mechanical properties of the HR3C steel change remarkably with annealing time due to the comprehensive effects of grain boundary strengthening, dispersion strengthening of precipitated phases and weakening of austenite matrix by precipitation in the annealing process. In the initial annealing stage （ 〈 500 h） , the high-temperature mechanical properties of the HR3C steel are nearly unchanged. As increasing the annealing time from 500 h to 1000 h, high-temperature tensile strength of the H R3C steel increases rapidly, however, plasticity of the steel decreases continuously. In the final annealing stage （ 〉 1000 h） , rnicrostructure of the HR3C steel does not change with the annealing time, so, both high-temperature strength and plasticity of the annealed steel remain to be unchanged. High-temperature tensile fracture mechanism of the HR3C steel changes from the normal mode to the shear mode as the annealing time increased.

关 键 词：HR3C耐热钢 高温时效 显微组织 高温力学性能 

分 类 号：TG142.73[一般工业技术—材料科学与工程]