7050高强铝合金断裂韧度K_(IC)值试验结果有效性影响因素分析

Analysis of factors influencing the validity of K_(IC) value test results of 7050 high strength aluminum alloy fracture toughness

平面应变断裂韧度K_(IC)是表征材料抵抗裂纹扩展的能力,是度量材料韧性好坏的一个定量指标,因此断裂韧度K_(IC)值测试数据的有效性和可靠性在实际生产检测中就显得尤其重要。针对日常检测工作中对K_(IC)值有效性影响较大的几个主要因素,对7050厚板、锻件CT试样进行断裂韧度K_(IC)测试,分析了不同试样厚度、试样方向及残余应力对断裂韧度试验结果有效性的影响。结果表明,这三个因素与K_(IC)值测试数据的有效性密切相关。本研究不仅分析了解了二者之间的关联性和规律性,而且还总结了试验参数选择对试验结果有效性的影响,为建立与完善相应材料的试验参数及满足材料K_(IC)检测和新产品开发的需要提供了试验经验和数据支撑。

Plane strain fracture toughness(K_(IC))is a quantitative index to measure the toughness of materials.Therefore,the validity and reliability of fracture toughness(K_(IC))values are particularly important in actual production and testing.In this paper,the fracture toughness K_(IC) test was carried out on CT samples of 7050 thick plates and forgings,and the effects of different sample thickness,sample direction and residual stress on the validity of the fracture toughness test results were analyzed.The results show that the three factors are closely related to the validity of K_(IC) test data.This study not only analyzed and understood the correlation and regularity between them,but also summarized the influence of test parameter selection on the validity of test results,providing experimental experience and data support for establishing and improving the test parameters of corresponding materials and meeting the needs of material K_(IC) detection and new product development.