ժҪ The influence of Ti on weld microstructure and mechanical properties in large heat input welding of high strength low alloy steels is investigated. The results indicate that a moderate amount of Ti is still effective for grain refinement even under larger heat input and a large amount of acicular ferrite (AF) is formed in the weld metal when Ti content is within 0.028%-0.038%. With increasing Ti content, proeutectoid ferrite in the weld metal decreases, whereas bainite and M-A constituent increase. The type of inclusion in the welds varies from Mn-Si-Al-O to Ti-Mn-Al-O and finally to Ti-Al-O as Ti content increases from 0 up to 0.064%. As for adding 0.028%-0.038% Ti, high weld toughness could be attained since most inclusions less than 2 ��m which contain Ti2O3 provide the effective nuclei for acicular ferrite formation. However, the toughness of the weld metals severely reduces when Ti content is over the optimum range of 0.028%-0.038%.
Abstract��The influence of Ti on weld microstructure and mechanical properties in large heat input welding of high strength low alloy steels is investigated. The results indicate that a moderate amount of Ti is still effective for grain refinement even under larger heat input and a large amount of acicular ferrite (AF) is formed in the weld metal when Ti content is within 0.028%-0.038%. With increasing Ti content, proeutectoid ferrite in the weld metal decreases, whereas bainite and M-A constituent increase. The type of inclusion in the welds varies from Mn-Si-Al-O to Ti-Mn-Al-O and finally to Ti-Al-O as Ti content increases from 0 up to 0.064%. As for adding 0.028%-0.038% Ti, high weld toughness could be attained since most inclusions less than 2 ��m which contain Ti2O3 provide the effective nuclei for acicular ferrite formation. However, the toughness of the weld metals severely reduces when Ti content is over the optimum range of 0.028%-0.038%.
��������:National High Technology Research and Development Project of China
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A-rong,Lin ZHAO,Chuan PAN,Zhi-ling TIAN. Influence of Ti on Weld Microstructure and Mechanical Properties in Large Heat Input Welding of High Strength Low Alloy Steels[J]. �й������ڿ���, 2015, 22(5): 431-437.
A-rong,Lin ZHAO,Chuan PAN,Zhi-ling TIAN. Influence of Ti on Weld Microstructure and Mechanical Properties in Large Heat Input Welding of High Strength Low Alloy Steels. Chinese Journal of Iron and Steel, 2015, 22(5): 431-437.
2015, Vol. 22 
