Grain separation

In forgingThe process of working metal to a desired shape by impact or pressure in hammers, forging machines (upsetters), presses, rolls, and related forming equipment. aluminum, rapid metal flow sometimes causes a separation or rupture of grainAn individual crystal in a polycrystalline metal or alloy.. Metal flow is affected by lubricantA material applied to dies, molds, plungers, or workpieces that promotes the flow of metal, reduces friction and wear, and aids in the release of the finished part., dieThe machined recess in a die that gives the forging its shape. and metal temperatureThe temperature of the forging stock just prior to forging., part shape, alloy, and hammerA machine that applies a sharp blow to the work area through the fall of a ram onto an anvil. The ram can be driven by gravity or power. See also Gravity Hammer and Power-Driven Hammer. operator technique; consequently, any one or combination of these factors can cause grain separationIn forging aluminum, rapid metal flow sometimes causes a separation or rupture of grain. Metal flow is affected by lubricant, die and metal temperature, part shape, alloy, and hammer operator technique; consequently, any one or combination of these factors can cause grain separation. The irregular crevices are seldom more than a few thousandths of an inch deep and can be removed by grinding or polishing.... More. The irregular crevices are seldom more than a few thousandths of an inch deep and can be removed by grinding or polishing.