小冲杆蠕变测试技术的研究综述

Review of Research on Small Punch Creep Test

小冲杆测试技术是一种评价材料性能的微型试样测试技术,可以确定材料弹性模量、屈服强度、塑性性能、抗拉强度、韧-脆转变温度、断裂韧性、蠕变性能等力学性能。该技术在新合金材料验证、焊缝热影响区性能描述、服役设备的剩余寿命预测等方面,得到各国学者的广泛关注和研究。其中,在材料蠕变性能的分析和预测方面,由于小冲杆蠕变测试技术具有表征全阶段单轴蠕变曲线的潜力,为高温服役设备蠕变性能评估及蠕变寿命预测提供了新的方法。小冲杆蠕变测试技术的理论和应用等方面已经取得了重要进展,但与传统蠕变测试方法相比,理论体系还不完善,在一些领域的应用尚处在探索和发展阶段,缺乏相关试验标准的指导,因此,有必要对现有研究成果进行系统分析和深入总结。基于现有国内外学者的相关研究成果,对小冲杆蠕变测试技术的试验系统、试样制备、试验操作、试验理论体系、有限元建模方法、试验结果处理、蠕变寿命分析方法等进行了综述;分析了目前该方法发展中的技术难题,对其未来发展趋势进行展望,以促进小冲杆测试技术的进一步发展。

The small punch testing method is a testing technique of miniature specimen for evaluating ma- terial properties,which is used for determining the mechanical properties of the material such as elastic modulus, yield strength, plastic behavior, tensile strength, ductile-brittle transition temperature, fracture toughness,creep behavior. This method has attracted much attention of and has been extensively by schol- ars of various countries in the aspects of validation of new alloy materials, behavior description of weld heat affected zone, residual life prediction of in-service equipment, etc. In the aspects of analysis and prediction of material creep behaviors, because the small punch creep test technology has the potential to characterize the full uniaxial creep curve,it provides a new method for analyze the creep behavior assessment and creep life prediction of high-temperature in-service equipment. Important progress has been made in the theol-y and application of the small punch testing method, but compared with the traditional creep tes- ting method, its theoretical system is not perfect, its application in some fields is still in the exploration and development stage with lack of guidance of relevant test standards. Therefore, it is necessary to ana- lyze and summarize the existing research results systematically. This paper reviewed the testing system, sample preparation, testing operations, test theory system, finite element modeling method, post-processing of test results, residual life prediction approaches, etc. of the small punch testing technology based on the relevant research achievements of scholars at home and abroad, analyzed the technical difficulties in the development of this method and prospected its future development trend in the hope to promote its further development.