摘要
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。
The cryogenic fracture toughness of 2A14T6 aluminum alloy welded joint（weld/fusion-line/ heat affected zone/base） at 77 K/4.2 K was studied by using the self-designed cryogenic extensometer and cryogenic testing system with the surface-crack method. The cryogenic fracture toughness was analyzed in terms of the fractography of the fracture surfaces. The results showed that the measuring system could be properly employed to measure the cryogenic fracture toughness KIQ. The obtained fracture toughness followed the sequence of base,heat affected zone, fusion-line zone, weld zone in large. Moreover, it was observed that the fracture toughness generally increased with the decrease of temperature except for fusion-line zone. The experimental results of the fracture toughness were well correlated with the fractography of the fracture Surfaces.
出处
《低温工程》
CAS
CSCD
北大核心
2007年第4期29-34,共6页
Cryogenics
基金
探月工程长征三号甲运载火箭可靠性增长项目资助
关键词
低温
位移传感器
断裂韧性
cryogenic
extensometer
fracture toughness
