Pressure cast lead‐calcium alloy positive grids for float applications can cause some unexpected service failures due to abnormal growth. Such failures have been interpreted as a result of irregular grain structure and weaker grain boundaries. Since lead‐calcium is a prcipitation hardening alloy, either heat‐treatment or controlled solidification can yield favorable grain size and distribution of precipitates in the matrix. The present investigation shows that controlled solidification of pressure cast grids can produce physically sound grids which are corrosion and growth resistant. Differences between industrial and automotive SLI grids cast by gravity and pressure casting techniques are revealed. The effect of casting temperature on the microstructure and anodic corrosion characteristics of lead‐calcium alloys ranging from 0.01 to 0.1% calcium content is also presented.