Common heat treatment processes include annealing, precipitation hardening, quenching, and tempering. Heat treatment techniques include annealing, case hardening, precipitation strengthening, tempering, carburizing, normalizing and quenching. Heat treatment techniques include annealing, case hardening, precipitation strengthening, tempering, and quenching. Common heat treatment processes include annealing, precipitation strengthening, quenching, and tempering. Heat treatment processes such as quenching and tempering can significantly change these properties, however. The first mainsprings were made of steel without tempering or hardening processes. In most instances the cryogenic cycle is followed by a heat tempering procedure. The embrittlement can often be avoided by quickly cooling the metal after tempering. Any cutting or grinding must be done prior to tempering. Tempering imparts the steel its flexibility and toughness according to the phase diagrams for steel. Cutting, grinding, and sharp impacts after tempering will cause the glass to fracture. Instead, a variation in hardness is usually produced by varying only the tempering time. Chocolatiering, the preparing of confections from chocolate, involves the techniques of tempering, molding and sculpting. Blending can have a pronounced effect on enhancing or tempering the wine's quality. The first stage of tempering occurs between room-temperature and .