包埋渗剂Al含量对渗铝N80套管钢渗层组织和性能的影响
史新勃
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作者单位:西安石油大学
中文关键字:N80套管钢;包埋渗铝;Al含量;渗层组织
英文关键字:N80 oil casing steel; pack aluminizing; Al content; aluminized layer microstructure
中文摘要:选用不同Al含量配比的渗铝剂,对N80套管钢进行包埋渗铝处理,形成渗铝层。阐述了包埋渗铝过程,并依次表征了不同Al含量渗剂所得渗铝层的金相组织、元素分布、物相组成和显微硬度。结果表明:采用不同Al含量的渗剂在950℃真空条件下可以在N80钢基体表面获得450~650µm厚度连续的渗铝层组织;渗铝层厚度随渗剂中Al含量增加而增厚;渗层组织从表面向基体方向Al含量呈梯度减少;渗剂中Al含量的不同引起渗层的物相变化,10%和20%Al含量的渗剂所得渗层组织为Fe3Al相,35%Al含量的渗剂所得渗层组织为FeAl相;不同Al含量渗剂下所得渗铝试样渗层组织的显微硬度均高于基体,从渗层表面向基体方向延伸,显微硬度逐渐降低趋于平缓。
英文摘要:Aluminized N80 oil casing steel was packed by different Al content of pack powder. The aluminizing process are introduced in this paper.The metallographic, element distribution, phase composition, microhardness of aluminized N80 casing steel were analyzed by using of optical microscope, scanning electron microscopy (SEM), X-ray diffraction (XRD), microhardness equipment in respective. There are several results can be concluded as following.(a) aluminizing layer with a thickness from 450 to 650µm can be obtained on the surface of N80 casing steel after high-temperature vacuum-pack processing by different Al content of pack powder. With the increase of Al content in the pack powder, the thickness of aluminizing layer increase. (b) From the surface to the matrix,the Al content gradiently decreases in the aluminized layer microstructure.The differential of Al content in the pack powder caused the different phase in the surface of aluminized layer. The Fe3Al phase were obtained with the Pack Powder of 10% and 20% Al content, but the 35% Al content Pack Powder get the FeAl phase.(c) The microhardness of aluminized layer microstructure with different Al content in the pack powder are higher than those of the microhardness of matrix. Microhardness gradually reduce and tend to constant from the surface to the matrix.