论文部分内容阅读
一、前言蠕变极限是评定耐热合金高温强度的一项重要指标。根据材料的工作条件,通常使用的蠕变极限有两种,一种是在规定温度(T)下引起规定的稳态蠕变速度(υ_2)的应力值。另一种是在规定温度下及规定试验时间(t)内引起规定蠕变伸长(δ_2)的应力值。在给定试验温度下,欲求得某种合金的δ_2-σ关系远较测定υ_2-σ关系复杂。因为υ_2-σ在对数坐标中呈直线关系,应力的改变使υ_2有规律变化,而σ引起δ的变化是无规律的。
First, the preface Creep limit is to assess the high temperature strength of heat-resistant alloy is an important indicator. There are two commonly used creep limits, depending on the material’s operating conditions, and one is the value of the stress that causes the specified steady-state creep rate (υ 2) at the specified temperature (T). The other is the specified temperature and the specified test time (t) caused by the provisions of the creep elongation (δ_2) stress value. At a given test temperature, the relationship of δ_2-σ for a given alloy is much more complicated than the determination of υ_2-σ. Because υ_2-σ has a linear relationship in logarithmic coordinates, the change of stress causes υ_2 to change regularly, and the change of δ caused by σ is irregular.