Remnant Life Assessment based on the Small Punch Test and the Wilshire Equations

Wilshire方程已被广泛应用于各种发电用合金钢和一些航空发动机用钛合金的单轴蠕变试验数据。在所有这些研究中，已经有可能从极短的加速单轴试验中获得准确的长期寿命预测。这表明，这些方程充分反映了主要的蠕变变形过程。然而，这种单轴测试不能在已经使用的部件上进行，而不会导致该部件结构完整性的恶化。小冲孔试验，即从使用中零件上切下薄片材料，已被提出作为确定剩余寿命的一种手段。1/2Cr1/2Mo1/4V钢的数值模型也表明，该测试对预先存在的损伤很敏感，因此提供了准确确定其剩余寿命的潜力。这些信息目前是无价的，因为英国的许多发电厂正在接近其最初的设计寿命，而英国国内日益增长的潜在能源缺口正在产生延长这些老化工厂使用的压力。***** SP和常规蠕变数据之间的相关性得到了改善，这对于支持之前在众多战略合作伙伴核心研究和研究生项目中生成的数据至关重要。＊＊＊＊＊

The Wilshire equations have been widely applied to uniaxial creep test data on a wide range of steel alloys used in power generation and on some Titanium alloys used in aero engines. In all these studies, it has been possible to obtain accurate long-term life predictions from very short-term accelerated uniaxial tests. This suggests that these equations adequately capture the main creep deformation processes.However, such uniaxial testing cannot be done on components already in use without causing a deterioration in the structural integrity of that part. The small punch test, that uses thin slices of material cut from in use parts, has been put forward as a means of determining remanent life. Numerical models on 1/2Cr1/2Mo1/4V steel have also demonstrated that this test is sensitive to pre-existing damage and so offers the potential to accurately determine this remanent life. Such information is currently invaluable as many power plants within the UK are approaching their original design lives, and the growing potential energy gap within the UK is creating pressure to extend the use of these aging plants.***** The improved correlation between SP and conventional creep data is ESSENTIAL to underpin data previously generated under numerous Stratigic Partnership Core Research and post graduate projects. *****