【摘要】 通过DSC404F3差式扫描量热法(DSC)研究了9Cr18马氏体不锈钢的固相线温度和液相线温度,通过对Thermo-Calc热力学模型进行分析,研究了在加热过程中材料的组织变化。在Thermecmastor-Z热模拟试验机上对热轧态和半固态坯料9Cr18不锈钢进行了触变压缩实验,根据所得结果绘制了应力-应变曲线。研究了两种9Cr18马氏体不锈钢在1 300℃,变形速率1 s-1,压缩变形率20%、40%和60%条件下的组织。结果表明,9Cr18马氏体不锈钢的固相线温度为1 279℃,液相线温度为1 413℃。热轧态原料液相大致沿原带状碳化物方向析出,容易导致液相在局部区域聚集阻塞,这种呈带状分布的液相不利于流动通道的畅通;半固态坯料液相在固相颗粒间流动,液相能够相互三维贯通,不会导致偏析等问题,保证了试样宏观形貌完整,只有少部分裂纹。更多还原

【Abstract】 The solid-phase line temperature and liquid-phase line temperature of 9Cr18 martensite stainless steel were studied by DSC404F3 differential scanning calorimetry(DSC),the structural changes of materials during heating were studied by analyzing Thermo-Calc thermodynamic model.The thixotropic compression experiment of hot-rolled and semi-solid 9Cr18 stainless steel was carried out on Thermecmastor-Z thermal simulation test machine,the stress-strain curve was drawn according to the results obtained.Microstructure of two kinds of 9Cr18 martensitic stainless steel were studied under the condition of the deformation rate of 1 s-1,compression deformation rate 20%,40% and 60%,at 1300 ℃.The results show that 9Cr18 martensitic stainless steel solidus temperature of 1279 ℃,the liquidus temperature of 1413 ℃.The liquid phase of raw materials in hot rolling state is precipitated roughly along the direction of the original ribbon carbide,which is easy to cause the liquid phase to gather and block in the local area.The liquid phase of semi-solid billets flows between solid particles,and the liquid phases are able to connect with each other in three dimensions without causing segregation and other problems,which ensures the integrity of macroscopic morphology of the sample with only a few cracks.更多还原