GTAW در روش جوشكاري برقي با تنگستن و گاز محافظ UDIMET سوپرآلياژ پايه نيكل 025 PWHT بررسي ترك ناشي از عمليانت حرارتي بعد از جوشكاري

STUDY OF PWHT CRACKING OF NICKEL BASE SUPER ALLOY (UDIMET 520) IN GTAW METHOD

In this paper, the mechanism and the cause and the ways for eliminating the decrease of PWHT cracking in welding of Nickel base super alloy (UDIMET 520) in GTAW method has been studied. For this study, XRD machine and quantometery has been used. Increasing of Al, Ti percentage and residual stress are the main causes of cracking PWHT. The results from quantometery tests demonstrate that decreasing tendency to PWHT cracking is due to the decrease of Al, Ti percentage of welding. Result of XRD tests show the tendency toward increasing of PWHT cracking for existing of strenghed residual stresses. Finally, it is illustrated that alloy welding Udimet 520 in TiG method is not sensitive to PWHT cracking.