History
of Metal CastingThe melting ovens of the early Iron Age can partly be traced back to ceramic burning ovens. The model and mould building was mastered very well from the beginning. Lost moulds made of loam and clay, wax models, single piece-work as well as permanent moulds made of stone and metal for the serial production of casting parts were already used. The production of hollow spaces by using cores, has already been proved by the oldest casting parts discovered.
- First machines were developed for " line-o-type " printing using Lead alloys.
- Die casting machines for engineered parts was developed in USA by Doehler. Patented in 1905.
- First machines were hand operated, often using compressed air directly on the metal, lead or zinc.
- Modern machines use hydraulics to develop high pressures (several thousand psi ) & very fast fill times.
- Cold chamber machines were developed for high melting point alloys Al, Mg, Brass, Stainless steel & Uranium.
Shortly
after the dark ages in Europe, the industrious sculptor and goldsmith,
Benvenuto Cellini began to make use of the lost wax method of casting.
He learned this process from the writings of the monk Theophilus
Presbyter (circa 1100) whose Schedula Diversarum Artium is the earliest
known foundry text. In Cellini's autobiography, considered to be one of
the classics of literature, he describes in great detail the casting of
his famous Perseus and the Head of Medusa. This three and a half ton
statue was completed in 1554 and was unveiled at the Loggia dei Lanzi in
Florence, Italy, where it stands to this day. During World War II, with urgent military demands overtaxing the machine tool industry, the art of investment casting provided a shortcut for producing near net shape precision parts and allowed the use of specialized alloys which could not be readily shaped by alternative methods. The investment casting process was found practical for many wartime needs--and during the postwar period it expanded into many commercial and industrial applications where complex metal parts were needed. It was in this period that the Hitchiner Manufacturing Company was founded at the Amoskeag Millyards of Manchester, NH.
The first successful shell technology was the Mercast Process, which used solidified mercury as a pattern material. Mercury patterns were very heavy but extremely accurate. This was a very difficult process as all pattern production and shell building had to be done at temperatures below minus 39 degrees Celsius--the melting temperature of mercury! This process is no longer used due to high costs and the health hazards involved in handling this toxic element.
Over 4,000 years ago, between the Tigrus and Euphrates Rivers in a land known as Mesopotamia, ancient artisans produced idols and ornaments using natural beeswax for patterns, clay for molds and manually operated bellows for stoking furnaces. Today, precision components for spacecraft and jet engines are investment cast using the latest advances in computer technology, robotics and countergravity casting techniques.