Microstructure and Mechanical Properties for TIG Welding Joint of High Boron Fe-Ti-B Alloy

Abstract

The hot rolled plates of high boron Fe-Ti-B alloys were butt-welded by gas tungsten arc welding (TIG) using base metal as the filler. The microstructures of the TIG weld joints were analyzed. The results indicate that the welding quality of the high boron Fe-Ti-B alloys is very good, there are no obvious defects such as cracks, lack of fusion, incomplete penetration and strip defects in the butt weld joints. The microstructures of the weld metal and th e heat affected zone are different from that of the base metal significantly. However, the micro-zone composition analysis indicates that the composition of the TIG weld joint is very uniform. Tensile tests were carried out on TIG welded joints after the post weld heat-treatment. The result shows that the welds have slightly higher yield strength (YS), and lower ultimate tensile strength compared to those of the base metal. However, the tensile properties reach a high level. The tensile strength of the high boron Fe-Ti-B alloys is higher than 580 MPa, and the yield strength is higher than 400 MPa.

Microstructure and wear of iron-based hardfacings reinforced with in-situ synthesized TiB2 particles

“…As is seen from the microstructure images, targeted TiB 2 phases were obtained in all microstructures. This situation was supported by current studies in the literature [3,19,[20][21][22][23][24][25], EDX analysis results (Table 5) and X-ray analysis results (Fig. 7) proved and supported the presence of TiB 2 in hardfacings.…”

Investigation of Hardfacing Deposits Obtained by Using Submerged Arc Welding Fluxes Containing High-Carbon Ferrochromium and Ferroboron

“…these phases forming in the microstructures were supported by XrD (Fig. 9), chemical composition analyses (taBlE 6), and the literature [4,6,9,[26][27][28][29][30], and it was determined that these and similar phases could be formed depending on the quantity of iron, chromium, boron, and carbon. Since a great majority of the studies in the literature were carried out by the arc welding techniques other than the submerged arc welding technique, the results of the present study were correlated with the results of studies carried out with different arc welding techniques and also a limited number of studies carried out with submerged arc welding technique.…”

“…Carbides and boro-carbides have hardness increasing effect, while austenite has a hardness-decreasing effect. thus, with the increasing rates of carbides and boro-carbides in the microstructures, hardness values increased, and accordingly this situation caused a decrease in the wear losses by increasing the wear resistance in parallel with the effect of the elastic modulus and friction coefficient [4,6,9,[26][27][28]. However, this comparison was carried out by ignoring the elastic modulus and friction coefficient.…”

“…thus, wear scratches formed in these types of hardfacing deposits mainly consist of continuous scratches, partially discontinuous scratches, and craters. Hardfacing deposits containing high percentage of chromium, carbon, and boron in chemical compositions have higher hardness values and higher abrasion resistances due to the high carbide and boro-carbide ratios in microstructures [26][27][28]. For this reason, wear scratches formed in these types of hardfacing deposits mainly consist of thinner continuous scratches, discontinuous scratches, and more crater cavities.…”