The effect of Al content on the corrosion resistance of Pb-Al alloys

Salt spray corrosion tests （SSCT） were utilized for evaluating the effect of Al content on the corrosion resistance in Pb-Al binary alloy. By weighing the weights before and after SSCT， the mass lost was got which reflected the corrosion resistance. When Al contents were 0.05% wt and 0.10%wt，respectively， the corrosion resistance were optimized compared Pb. Whereas， increasing the Al content to 0.15%wt， the corrosion resistance has no apparently improve. The optical microscope was used for observing the microstructure. When the content of Al was 0.05%wt and 0.10%wt respectively， the number and size of gully and pit etching were declined compared with pure Pb. However， when the Al content increased to 0.15%wt， the gully and pit etching were enlarged， whether number or size， the corrosion resistance had no obviously improvement on this occasion.