Laser Welding of BTi-6431S High Temperature Titanium Alloy

Abstract

Abstract:A new type of high temperature titanium alloy, BTi-6431S, has recently become the focus of attention as a potential material for aircraft engine applications, which could be used up to 700 • C. Pulsed laser welding was used to butt join the BTi-6431S titanium alloy in order to understand the feasibility of using fusion-based welding techniques on this material. The effect of laser energy on the microstructure and mechanical properties of the joints was investigated. The microstructural features of the joints were characterized by means of microscopy and X-ray diffraction. Tensile testing was conducted at both room temperature and high temperature to simulate potential service conditions. The results show that the microstructure of the laser welded joints consists of primary α phase and needle α' phase, while the microstructure of the heat affected zone consists of α, β, and needle α' phases. The tensile strength of the welded joints at room temperature was similar to that of the base material, despite a reduction in the maximum elongation was observed. This was related to the unfavorable microstructure in the welded joints. Nonetheless, based on these results, it is suggested that laser welding is a promising joining technique for the new BTi-6431S titanium alloy for aerospace applications.

Laser Oscillating Welding of TC31 High-Temperature Titanium Alloy

“…The BM consists of elongated α grain and intergranular β grain (Figure 7a). A large amount of acicular Ti and columnar prior β grain boundaries can be observed in the FZ as shown in Figure 7b,c, which implies that the prior β phase gradually transform into the secondary α phase [1,29]. The phases in the FZ of the welded joints are examined by XRD.…”

Laser Welding

“…The present special issue on "Laser Welding" was a success with a total of 16 original research works published after peer-review. Different topics were discussed within this special issue: modelling and simulation of laser welding were presented in [1][2][3][4]; porosity control by means of high speed imaging and microscopy techniques was studied and discussed [5]; the effect of processing parameters on the microstructure and mechanical properties of laser-welded joints was evaluated for different metallic systems such as AZ31 alloy [6], steels [7][8][9][10], Ti-based alloys [11][12][13], and Al-based alloys [14]; and finally, dissimilar laser welding of aluminum to steel was presented [15,16].…”

Design and Experimental Study of HTSG for Waste to Energy: Analysis of Pressure Difference

“…Extensive research on materials has been recently conducted to overcome this challenge. Zieliński et al [9] introduced a material with an austenitic structure (HR6W, Sanicro 25) that has stability up to 750 • C. In particular, Sanicro 25 was proven to remain stable for more than 2000 h at 700 • C. Zeng et al [10] investigated the tensile properties, microhardness, chemical composition distribution, and microstructure of the BTi-6431S titanium alloy, which can be used in applications up to 700 • C. Furthermore, Wright et al [11] examined the properties of Alloy 800H and Alloy 617 for nuclear plants and asserted that their operating temperature range was 750-800 • C in the steam generator. Dewa et al [12] also analyzed the fatigue properties of Alloy 617 and stated that its maximum design temperature was 950 • C.…”