反应堆压力容器用低合金钢焊丝焊态熔敷金属疲劳性能研究

采用一种免焊后热处理的回火焊道焊接工艺在碳钢试板上进行反应堆压力容器用低合金钢焊丝堆焊工艺试验,获取低合金钢焊丝焊态熔敷金属。根据ASTM E466和ASTM E606标准对焊态熔敷金属进行室温下低周和高周疲劳性能试验,并使用Coffin-Mansion方程与三参数方程拟合焊态熔敷金属低周疲劳和高周疲劳寿命曲线。同时,根据核电设备设计规范RCC-M中推荐的修正系数对试验获得的疲劳曲线进行修正,获得修正后的S-N曲线,并与RCC-M规范中低合金钢疲劳设计曲线进行对比。试验结果表明:基于RCC-M修正后的焊态熔敷金属低周疲劳S-N曲线与RCC-M中的低合金钢低周疲劳设计曲线基本重合;基于RCC-M修正后的焊态熔敷金属高周疲劳S-N曲线位于RCC-M中的低合金钢高周疲劳设计曲线之上。

Fatigue property study of as-welded deposited weld metals used in reactor pressure vessel

A temper bead welding procedure without postweld heat treatment is performed at the carbon steel testing coupon to obtain as-weld deposited metal using the low alloy steel wire which is usually employed for the reactor pressure vessel.The low cycle fatigue test and high cycle fatigue test of as-weld deposited metal at room temperature are performed according to ASTM E466 and ASTM E606,and the low cycle fatigue curve and high cycle fatigue curve are constructed by means of Coffin-Mansion Equation and Tri-parametric Equation.Meanwhile,low cycle fatigue curve and high cycle fatigue curve are further revised according to the correction method recom-mended in RCC-M code which is employed for nuclear power equipment design.In addition,the revised S-N curves are compared with the design fatigue curve of low alloy steel specified in RCC-M code.The result shows that the revised SN curve(low cycle fatigue)of deposited metal basically coincides with the design curve(low cycle fatigue)specified in RCC-M code,the revised S-N curve(high cycle fatigue)of deposited metal is above the design curve(high cycle fatigue)specified in RCC-M code.