摘要
Abstract
The effect of sensitizing treatment on the microstructure and the mechanical properties of 2205 duplex stainless steel was studied by means of optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and mechanical property testing. The results show that the σ phase and the χ phase are precipitated at the boundaries ferrite/austenite and fer-rite/ferrite under sensitizing treatment at 850℃ , and the precipitated phase content increases with increasing of sensitizing treatment time. Sensitizing treatment leads the increase of the strength and dramatic decrease of the plasticity. The tensile fracture surfaces are characteristic of cleavage and facet, and the second cracking exists on the main fracture surface as the sensitizing treatment time increases. When sensitizing treatment time is 2h, the impact toughness of the samples at room temperature decreases from 290J to 10J. The impact fracture surfaces are changed from dimple to cleavage. The decrease of the impact toughness can be attributed to appearance of the precipitated phase.关键词
2205双相不锈钢/敏化处理/析出相/力学性能Key words
2205 duplex stainless steel/ sensitizing treatment/ precipitated phase/mechanical property分类
矿业与冶金
