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GH2132 alloy is a high-temperature alloy that is widely used in aviation, aerospace, energy and other fields. Due to its excellent mechanical properties and high temperature resistance, GH2132 alloy is prone to cracks during the welding process, which not only affects the welding quality, but also may pose a threat to structural safety. Therefore, it is of great practical significance to analyze the welding cracks of GH2132 alloy, the causes of them and the preventive measures.
1. GH2132 alloy welding crack type.
GH2132 alloy welding cracks mainly include hot cracks, cold cracks and reheat cracks.
1.Thermal cracking.
Thermal cracking is a crack produced under welding stress during the welding process due to the reduced crack resistance of the material at high temperatures. Thermal cracks mostly occur near the fusion line of the weld and show obvious twists and irregular shapes.
2.Cold cracks.
Cold cracks are cracks that occur at lower temperatures after welding is completed due to the action of welding stress during the cooling process. Cold cracks usually occur in the weld heat-affected zone and sometimes inside the weld.
3.Reheat cracks.
Reheat crack is a crack that occurs after the weldment is heated to a certain temperature after the welding is completed. The occurrence of this crack is related to factors such as the welding material, heating temperature, and heating speed.
2. Causes of welding cracks in GH2132 alloy.
The causes of GH2132 alloy welding cracks mainly include the following aspects:
1.Influence of alloying elements.
GH2132 alloy contains a large number of alloying elements, such as AL, Ti, etc., which are easy to react with oxygen, nitrogen and other gases during the welding process to form oxides and nitrides with low melting points, resulting in the generation of hot cracks.
2.Effect of welding stress.
GH2132 alloy is subjected to welding stress during the welding process, and cracks occur when the welding stress exceeds the crack resistance of the material. The welding stress mainly includes the shrinkage of the weld pool, the change of the binding degree and the change of the temperature gradient.