结晶器铜板镀层表面组织结构及工艺性能研究

发布时间：2018-08-18 13:54

【摘要】：在连铸连轧过程中,结晶器是一个称为“心脏”的重要部件。提高结晶器的使用寿命就可以节约连铸连轧的成本。本文先采用单一变量法,研究了工艺参数对Ni-Co合金镀层硬度的影响规律,优化确定了电沉积Ni-Co合金镀层的最佳工艺条件,并在铬-锆-铜上制备出了硬度高、结合性能良好的Ni-36.97%Co合金镀层。分析比较退火温度对Ni-36.97%Co合金镀层显微硬度及结构的影响规律,发现:随退火温度的升高,合金镀层的硬度呈现先提高后降低,300℃时最高。退火后镀层呈现较强的(111)织构;采用XRD对退火镀层进行物相分析,结果表明镀层中产生了CoO硬质相。之后向Ni-36.97%Co合金镀层的镀液加入Fe元素来研究工艺参数、Fe含量、退火温度对Ni-Co-Fe合金镀层的影响,得出最佳的工艺参数。研究发现,Ni-Co-Fe合金镀层的显微硬度随热处理温度升高先提高后降低,350℃时达到最高值,存在明显的退火强化现象。镀层晶粒尺寸在350℃之前缓慢增加,随后急剧增大,且达到微米级别。衍射峰(111)和(200)随热处理温度的升高不断锐化,且(111)晶面织构择优取向程度越大。采用XRD对Ni-Co-Fe合金镀层进行物相分析,结果表明,热处理后镀层有析出物产生且衍射图谱表现出来的主要聚集在(111)与(200)衍射峰间,热处理后Ni-Co-Fe合金镀层的强化机理是由于硬质相的析出。镀态的Ni-Co-Fe合金镀层的强化机理是由于镀层中存在硬质相FeNi3、Co3Fe而使硬度增大。研究发现电沉积时间并没有改变Ni-Co-Fe合金镀层(111)晶面的择优取向,但随电沉积时间的增长,晶粒尺寸有所变小。
[Abstract]:During continuous casting and rolling, the crystallizer is an important component called the heart. Increasing the service life of the mould can save the cost of continuous casting and rolling. In this paper, the influence of process parameters on the hardness of Ni-Co alloy coating was studied by single variable method. The optimum process conditions for electrodeposition of Ni-Co alloy coating were optimized, and high hardness was prepared on Cr-Zr-Cu coating. Ni-36.97%Co alloy coating with good properties. The effect of annealing temperature on the microhardness and structure of Ni-36.97%Co alloy coating is analyzed and compared. It is found that the hardness of Ni-36.97%Co alloy coating increases first and then decreases at 300 鈩，

本文编号：2189671