显微组织对TC16钛合金棒丝材冷镦成形性能的影响

Effect of Microstructures on Cold Heading Formability of TC16 Titanium Alloy Bar and Wire

TC16钛合金棒材在冷镦成形方面具有较大的加工和应用优势,棒材组织形貌对最终紧固件冷镦成形性有直接影响。采用不同加工方式、不同变形温度和热处理制度获得了不同组织状态的TC16钛合金小规格棒丝材,通过紧固件冷镦成形实验,研究了显微组织对冷镦成形性能的影响。结果表明,TC16钛合金丝棒材冷镦过程中的组织变形主要是纵向金属扁平化和破碎挤压的过程;纵向为等轴组织或者网篮组织的TC16钛合金棒丝材,在冷镦过程中纵向变形均匀,冷镦过程顺利;纵向为拉长组织的TC16钛合金棒丝材在冷镦过程中易产生裂纹。

TC16 titanium alloy bars have superior advantages in processing and application of the cold heading formability. The microstructure has great influence on cold heading formability of final fasteners. The TC16 titanium alloy bars and wires with different microstructures were obtained through different processing methods, deformation temperatures and heat treatments. The effect of microstructures on cold heading formability were analyzed through cold heading forming experiments. The results show that microstructures of TC16 titanium alloy bars and wires are intensively crushed and extruded during cold heading, the bars and wires with longitudinal equi-axial or basketwave microstructure can be cold headed successfully and the deformation is more homogenous, while the bars and wires with longitudinal elongated microstructure tend to be cracked when cold headed.