| 690 is used as a mold material in the glass container industry and other high temperature controlled heat transfer applications with severe wear conditions at elevated temperatures. Although slightly more susceptible to sulfur corrosion than 700XX, the ability to maintain consistent linear expansion during the heating and cooling cycles makes alloy 690 the perfect choice for glass container bottle molds. 690 has a time proven ability to resist corrosion in the glass making environment. When using 690, avoid using sulfur based swabbing compounds as release agents in either the blank or finish operation. Compounds used on the blank side will generally carryover to the finish side. When swabbing compounds containing sulfur are used in repeated production cycles, the sulfur will attack the aluminum and an orange peel texture will develop on the casting surface. Information provided by Erie Bronze & Aluminum Co. |
