Effects of Cryogenic Treatment after Annealing of Ti-6Al-4V Alloy Sheet on Its Formability at Room Temperature

Abstract

In this article, the effects of cryogenic treatment after annealing on the formability of Ti-6Al-4V alloy sheet were experimentally studied. The Ti-6Al-4V titanium alloy was treated by cryogenic treatment after annealing (ACT). Tensile tests were carried out using a universal machine at room temperature. The microstructure evolution of Ti-6Al-4V subjected to ACT was also investigated using an optical microscope (OM). Both the shearing performance and drawing formability were analyzed by punch shearing tests and deep drawing tests, respectively. Results showed that after ACT, the tendency of the β phase can be apparently changing into stable β' and α' phases. The elastic modulus is lower than that of the untreated material. It was found that both the yield strength and tensile strength are declined slightly, whereas the ductility is increased significantly. The shear strength in punch shearing is decreased at room temperature and cryogenic temperature. The ratio of smooth zone on the section after ACT3 is much larger than the others. The rollover diameters are not obviously greater than those of the untreated. Additionally, the height of the burr shows a decreasing trend after ACT. During deep drawing, drawing depth is deeper than that of the untreated material, the drawing load after ACT is reduced, and the decreasing tendency of the drawing load slows down. It is noted that the micro-cracks occur at the bottom of the sample.

The Effects of Temperature on Microstructure and Formability of Titanium Alloys

“…Daha sonra çekme derinliğinin diğer numunelerde yine kademeli olarak azaldığı gözlemlenmiştir. Bu durum, ısıl işlemin ve kriyojenik işlemin numunelerin elastise değerlerini düşürmesiyle, çekme ve akma mukavemetleri üzerinde pozitif etkiler oluşturmasıyla açıklanmıştır [30]. [36].…”

Cryo treatment and corrosion studies of nickel-titanium shape-memory alloy

“…For this reason, electro discharge machining (EDM), which has a distinct mechanism for material removal, is often used for its machining. [13][14][15][16] Few studies have been done on cryo treatment of NiTi SMA. [17][18][19][20][21][22][23] However, no study has been performed on the corrosion properties and mechanical properties of deep cryo treatment of NiTi.…”

“…For this reason, electro discharge machining (EDM), which has a distinct mechanism for material removal, is often used for its machining. 13–16…”

Improving scratch-resistance and wear-resistance of VN film by deep cryogenic treatment with liquid nitrogen

“…Deep cryogenic treatment (DCT), as one of the effective methods to improve materials' properties, has been shown a considerable application prospect in the fields of aerospace, cutting tool and manufacturing industries [1,2]. In academia, DCT has been applied to tool steels [3][4][5], cemented carbides [6,7], Ti-based alloys [8][9][10], Mg-based alloys [11,12], Al-based alloys [13][14][15] and composites [16][17][18], to study the effect on the microstructure evolution and properties transform. To our knowledge, by DCT, the service performance of the coating/film can be also abstractly improved, to a certain extent.…”