加热温度对热轧复合钛/不锈钢板结合性能的影响

Effect of Heating Temperature on the Bonding Property of the Titanium/Stainless Steel Plate by Hot-Rolling Bonding

摘要:

利用热模拟试验机进行了加热温度分别为800、850、900、950 ℃的纯钛TA2与304L不锈钢的压缩复合实验，并从中选取最佳加热温度进行了热轧复合实验。利用金相显微镜、电子探针、XRD物相分析等手段对复合界面处的微观形貌、元素的扩散及金属间化合物的种类等进行了分析研究，并对界面的剪切强度进行了测试。实验结果表明，TA2/304L界面处生成了σ相、σ′相、FeTi、NiTi和CrTi4等金属间化合物。随着温度的升高，金属间化合物层的厚度增加。界面剪切强度随金属间化合物厚度增加而减小。加热温度为850 ℃时，热模拟试样获得最佳结合性能，热轧复合实验获得的钛/不锈钢复合板界面的剪切强度达到215 MPa。

Abstract:

Compressing bonding tests between pure titanium TA2 and 304L austenitic stainless steel have been carried out with the heating temperature 800, 850, 900, 950 °C by a thermal simulation machine. And then hot-rolling bonding test has been performed with the best heating temperature derived from the thermal simulation test results. The microstructure of the interfaces has been analyzed by optical and scanning electron microscopy (SEM). The interdiffusion of the elements and the reaction products at the interfaces have been evaluated by electron probe microanalysis (EPMA) and X-ray diffraction technique. And the shear strengths have been tested by a universal testing machine. Results show that the diffusion zone is dominated by σ-phase, σ′-phase, FeTi, NiTi and CrTi4. With a rise in the heating temperature the shear strength of the interface drops owing to an increase in the width of reaction products. The thermal simulation test sample heated at 850 °C gets the highest shear strength of about 147.5 MPa. And shear strength of the hot-rolling bonding plate heated at 850 °C is as high as 215 MPa.