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Numerical methods are used to investigate the changes in the thermomechanical state of the region of the welded joint in dissimilar steels in a wide temperature range. The effect of edge preparation of the welded joint on the formation of residual stresses and strains in the welded joint in two-layer steels with different physical–mechanical and service properties is investigated. The calculation results are in agreement with the experimental data. 相似文献
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热壁加氢反应器堆焊层裂纹的检测与监测 总被引:1,自引:0,他引:1
叙述加氢反应器堆焊层裂纹的检测技术和在不卸催化剂的情况下,从外壁进行检查并对堆焊层裂纹的高度进行监测的研究成果。该技术经实验验证,具有较高的精度,结果比较理想。 相似文献
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Krzysztof Krasnowski 《Welding International》2013,27(9):668-671
Microcracking susceptibility in the dissimilar multipass weld metal of alloy 690 and low-alloy steel A533B was evaluated, and the effect of dilution on hot cracking (ductility-dip and liquation cracking) behaviour was investigated. In order to simulate the dissimilar multipass weld metal of alloy 690 to A533B steel, the A533B plate was welded under various dilution ratios using alloy 690 filler metal with different contents of P and S. Several weld metals, which had different alloy compositions at the fixed (P+S) content, were manufactured, and then ductility-dip and liquation cracking susceptibilities of the reheated weld metals were evaluated by the spot-Varestraint test. Ductility-dip cracking susceptibility heightened as the dilution ratio was increased even when the amounts of P and S were fixed. The increased dilution ratio (contamination of Fe into the weld metal) should reduce the tortuous character of the grain boundary (GB) due to inhibiting the constitutional supercooling (the instability of the solidification boundary), as well as enhance the GB embrittlement due to promoting the GB segregation of P and S. Furthermore, the liquation cracking susceptibility slightly heightened with an increase in the dilution ratio at the fixed (P+S) content. The increased liquation cracking susceptibility would be attributed to the enhancement of solidification segregation of P and S with increasing the dilution ratio. 相似文献
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The efficiency of replacing VDU-506 welding equipment with the PDGO-5278 wire feed system by the FastMig KM500 power source and the MF33 wire feed system supplied by Kemppi Oy is confirmed. 相似文献
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