||Alloy No. 701
Johnson Matthey's P40 is a 4% silver-tin soft soldering alloy. P40 has excellent soldering characteristics and offers a number of advantages over conventional tin-lead alloys. It provides improved strength characteristics particularly where service at moderately elevated temperatures is a factor.
Being lead free, P40 may be used in plumbing installations, particularly where soft water is in use. P40 is widely used in food handling equipment where lead contamination must be avoided.
P40 is a good colour match on stainless steel and the resulting joints are not prone to interfacial (crevice) corrosion. The optimum joint gap for P40 is 0.075mm.