Effect of Cr Content on Technology and Properties of Ti Alloy for Automobile

In this paper,the influence of Cr content on the microstructure and properties of TC4 alloy was studied.The results show that the Cr element can decrease the transition temperature of β phase in TC4 alloy.When the Cr content is lower than 3% TC4 alloy possesses duplex microstructure,while the phase transition of TC4 alloy is completed and the α phase continuously distributes in the boundaries of β phase with Cr content higher than 3%.The α and β phases coexist in the TC4 alloy with different Cr contents,and the content of β phase obviously increases with increase in Cr content.Both the tensile strength and yield strength of TC4 alloy gradually increase while its elongation percentage decreases,with increase of Cr content.When the Cr content is 4%,the TC4 alloy respectively has a maximum tensile strength and yield strength of 1 068 and 1 697 MPa,as well as a minimum elongation percentage of 9.94%.