氮对高强度耐候钢钒析出行为的影响

Effect of Nitrogen on the Vanadium Precipitation Behavior of Higher Yield Strength Weathering Steels

在普通耐候钢的基础上采用单独添加或复合添加微合金元素的方法生产高强度耐候钢,并结合攀枝花现有资源特点,针对性地进行了不同氮含量含钒高强度耐候钢的研究。采用Glbeele-3500热模拟试验机、相分析等方法,研究了含钒高强度耐候钢在不同变形程度及变形温度条件下的钒析出-温度-时间关系(PTT曲线),探讨了氮含量、变形量对钒析出行为的影响。试验表明,试验钢的PTT曲线为典型的C曲线形状,在一定的奥氏体化条件下,钒析出过程存在所需时间最短的析出温度;增加氮含量会使PTT曲线明显向左移动;增加变形量可以加快V(C,N)在奥氏体中的析出过程,使PTT曲线向左移动;变形量越大,析出开始时间越短。通过研究,为进一步产品开发提供了技术支持。

The separate addition or combined addition of microalloy elements based on common weathering steel is usually applied in producing higher yield strength weathering steels. The target-oriented researches on the vanadium-containing weathering steels were conducted in this paper that combined with the advantage of vanadium resource at Panzhihua Iron Steel（ Group） Co.. Methods such as Glbeele-3500 thermal simulated test machine,phase analyzing,and so on were used to investigate the vanadium precipitation amount – temperature-time（ PTT） of test samples with different deformation degree and nitrogen content. The relationship between the amount of vanadium precipitates,temperature and precipitate time was analyzed. It has been found that the PTT curves of test samples with the same austenite amount are C curve shape,a shortest time of precipitation along with the vanadium precipitation process is also been found. Increase the nitrogen content will make PTT curve move to the left obviously. Additionally,increasing deformation degree can accelerate the rate of V（ C,N） particle precipitation in the austenite,make PTT curve move to the left obviously. It has been also found that the more deformation degree,the shorter start time of the V（ C,N） particle precipitation. The study offers the essential technical support for the further development of products.