摘要:

AbstractThe influence of Cu, Kovar, Mo, and W interlayers on the magnitude and distribution of thermal stresses and on the tensile strength of brazed Si3N4−steel joints is examined using a combination offinite element modelling (FEM) calculations and direct experiment. The FEM takes into account plastic flow and changes of mechanical properties of the interlayer, the steel substrate, and the filler metal as temperature decreases following the brazing operation. Joints made using low yield strength/high ductility interlayers, such as Cu, have lower thermal stresses and higher strengths than those made using low thermal expansivity/high yield strength interlayers, such as Mo or W. A composite interlayer comprising Cu and W will produce the lowest thermal stresses during brazing. Increasing the thickness of the interlayer decreases the thermal stresses produced during brazing, since the rigid restraint effect due to the high yield strength/high elastic modulus steel substrate is reduced.MST/1442

ISSN:0267-0836    

DOI:10.1179/mst.1991.7.9.863

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractThis paper investigates systematically the effect of pulse conditions, type of shielding gas, and wire composition on blowhole and spatter formation and on wire melting rate to obtain guidelines for selection of welding conditions. It was found that spatter formation can be reduced significantly by using a shielding gas of composition Ar + 2·4%O2+20% CO2for pulsed gas shielded metal arc (MAG) welding. It was also found that it is possible to reduce blowhole formation using pulsed MAG welding. However, blowhole formation is affected greatly by variations of pulse condition and by shielding gas composition.MST/1423

ISSN:0267-0836    

DOI:10.1179/mst.1991.7.9.869

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

ISSN:0267-0836    

DOI:10.1179/mst.1991.7.9.877

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor