论文部分内容阅读
为了研究2A14T6铝合金焊接接头(焊缝/熔合线/热影响区/母材)的低温(77 K/4.2 K)断裂韧性,采用表面裂纹法,通过自主研制的低温位移传感器及力学测试系统得到了断裂韧性KIQ性能参数,并结合断口具体分析了形貌与断裂韧性的关系。研究结果表明:该测试系统能够有效的测量材料的低温表面裂纹断裂韧性KIQ;无论在室温还是低温下,焊接接头不同区域的断裂韧性大致为母材>热影响区>熔合线>焊缝;除熔合线变化不明显外,各区域的断裂韧性随温度的降低而增加,呈现较好的规律性;微观断口形貌与断裂韧性试验测试结果有较好的一致性。
In order to study the low temperature (77 K / 4.2 K) fracture toughness of 2A14T6 aluminum alloy welded joint (weld / fusion line / heat affected zone / base metal), the surface crack method was adopted to obtain the low temperature displacement sensor and mechanical test system Fracture toughness KIQ performance parameters, combined with fracture analysis of the specific morphology and fracture toughness. The results show that the test system can effectively measure the fracture toughness KIQ of low-temperature surface cracks of the material. The fracture toughness of the different regions of the welded joints is roughly that of the base metal> heat affected zone> weld line> weld at either room temperature or low temperature. The fracture toughness of each region increases with the decrease of temperature, showing a good regularity. The results of microscopic fracture morphology and fracture toughness test are in good agreement.