钢板热浸镀55%Al-Zn合金镀层的组织及其形成过程

热镀55%Al-Zn合金(GL)的组织结构对稳定GL镀层质量、提高其性能至关重要,以往对其组织结构的变化规律研究不够。采用金相法和扫描电镜观察了GL镀层的组织结构,分析了镀层组织中各相的形成过程。结果表明:镀层由2部分组成,一层为Al-Zn合金层,一层为钢板与Al-Zn合金层之间的过渡层;Al-Zn合金层的组织包括65%左右的树枝晶、30%左右位于树枝晶间的偏析组织以及5%的富硅相粒子,过渡层主要为Zn和Si原子以置换固溶的形式溶入到FeAl3中形成的固溶体。

热浸Zn-Al合金镀层的助镀工艺和显微组织特征

简述了热浸Zn-Al合金镀层的助镀工艺和性能评价指标特点,论述了钢材热浸镀Zn-Al合金镀层的组成及形成过程,分析了钢中Si、Mn、P等常存元素对Zn-Al合金镀层中金属间化合物形成的影响,指出了热浸Zn-Al系多元合金镀层今后的研究方向。

铜浸镀锡层形成过程分析

以硫脲作为电位调整剂,以甲烷磺酸锡为主盐的酸性溶液作为镀液,采用浸镀法在铜基材上制备了锡镀层。采用场发射扫描电子显微术(FESEM)和X射线衍射(XRD)表征锡镀层的组织结构,根据数码相机微距照片进行宏观分析。研究表明,该镀液体系浸镀锡可以获得光滑而致密的浸锡层,无枝晶形成。该镀层主要相结构为体心四方的白锡。镀层的形成可分为锡晶粒的剧烈瞬间形核、平面层状生长和镀层致密化排列3个阶段。

Formability of aluminum-silicon coated boron steel in hot stamping process

Flow behavior of the Al-Si coated boron steel was investigated with Gleeble-3500,in comparison with the uncoated one.Effect of deformation conditions on the coating integrity was characterized by optical microscopy.Facture surfaces of the coated steels were inspected under SEM.Experimental results indicate that the ultimate tensile strength and ductility of the Al-Si coated boron steel are lower than those of the uncoated steel under test conditions.Extensive cracks occur in the coating after tensile tests;the width and density of cracks are sensitive to the deformation temperatures and strain rates.The bare substrate exposed between the separate coating segments is oxidized.Appearance of the oxide degrades the Al-Si coating adhesion.Remarkable difference between formability of the coating layer and the substrate is confirmed.The formability of the Al-Si coating could be optimized by controlling the phase transformation of the ductile Fe-rich intermetallic compounds within it during the austenization.

铜浸镀锡层的宏、微观形貌形成过程

以硫脲作为电位调整剂,以甲烷磺酸锡为主盐的酸性溶液作为镀液,采用浸镀法在铜基材上制备了锡镀层。采用场发射扫描电子显微术(FESEM)和X射线衍射(XRD)表征锡镀层的组织结构,数码相机微距照片表征镀层的宏观形貌。研究表明,该镀液体系浸镀锡可以获得光滑而致密的浸锡层,无枝晶形成。该镀层主要相结构为体心四方的白锡。镀层的形成可分为锡晶粒的剧烈瞬间形核、平面层状生长和镀层致密化排列3个阶段。