摘要
对国内不同厂家生产的X90直缝埋弧焊管进行了静拉伸试验,分析了管线钢的加工硬化性能。结果表明:X90直缝埋弧焊管的拉伸曲线具有连续屈服特征,没有明显的屈服平台,属于典型的Round house型曲线。真应力-真应变的双对数曲线在整个范围内不能近似为一条直线,在整个塑性变形区域内不完全符合Hollomon公式,不具有确定的加工硬化指数。但表现为三个阶段的加工硬化,第一阶段和第三阶段具有确定的加工硬化指数(分别记为n1和n2),n1<n2。在忽略试样不均匀性及试验误差的前提下,随屈强比的升高,均匀延伸率、加工硬化指数均呈现下降趋势。
The static tensile tests were conducted for X90 SAWL pipes produced by different China domestic manufacturers, and the strain-hardening performance of pipeline steel was analyzed. The results indicated that the tensile curve of X90 SAWL pipes has no significant yield platform, it belongs to the typical Round house curve. The double logarithmic curve of the true stress and strain cannot approximate to a straight line within the whole scope, in the plastic deformation area not completely comply with Hollomon formula, not with determined strain-hardening indexes. But the strain-hardening indexes of X90 pipes has three stages, the first and third stages are with determined strain-hardening indexes（marked as n1 and n2）, and n1 is less than n2. Under the condition of ignoring the non-uniformity of samples and the experimental error, the uniform elongation （UEL） and strain-hardening indexes respectively shows a downward trend with the increase of yield ratio.
出处
《焊管》
2015年第4期11-14,20,共5页
Welded Pipe and Tube
基金
陕西省自然科学基础研究计划资助项目(项目编号:2011JQ6017)
关键词
焊管
X90钢
静拉伸
屈强比
均匀延伸率
加工硬化指数
welded pipe
X90 steel
static tensile test
yield ratio
uniform elongation
strain-hardening index
