N6纯镍丝表面裂纹的研究

On Surface Cracks of Pure Nickel Wire

本文针对某厂生产的纯镍N6线材及成品铆钉表面出现的裂纹,对其进行分析。通过使用S-520型扫描电镜观察裂纹中出现的夹杂物,从其形貌及能谱的分析确定其中包含Al、Si、Ca等成分;然后使用EPMA1600型电子探针进行进一步验测,发现试样中的夹杂物含有大量的O、C、S等元素,充分说明试样中的夹杂物是以复合氧化物的形式存在。为了更准确的判断夹杂物的类型,将试样放在金相显微镜下,通过不同的视场发现其中的夹杂物包含有硅酸盐类。为了避免在制样时对成品本身夹杂物的影响,用电解分离法将试样进行电解,把电解所得的非金属夹杂物进行分离,然后进行能谱分析,发现结果与以上检测结果一致。综合以上各种检测手段,结果表明:纯镍N6线材内部和表面存在的大量非金属夹杂物是形成裂纹的主要原因。

The cracks occurred on the surface of pure Ni wire N6 and its products（rivets）were analyzed. The inclusions in the cracks were observed by using S-520 scanning electronic microscope and Al,Si,Ca, etc elements in the inclusions were analyzed by energy spectrum analysis. EPMA1600 type electronic probe analyzer were used to elemental analysis. It＇s discovered that elements such as O,C,S etc exist in the inclusions. All of above indicated the inclusions in the samples may be composed of compound oxides. In order to identify the type of impurities, samples were observed at polarized light by metallographic microscope and silicate was found in impurities. To avoid the effects of preparing samples process on the impurities, theinclusions were separated by electrolytic separation method. The prepared non-metal impurities were also analyzed by energy spectrum analysis, andsimilar conclusion were made. Combining above different detective ways, the results show that a great deal of non-metal impurities existing in the inner and surface of pure Ni wire N6 is the main reason producing the cracks.