It is generally agreed that the first known metals were gold, silver, and copper, which occurred in the native or metallic state, of which the earliest were in all probability nuggets of gold found in the sands and gravels of riverbeds. In foundries liquid steel is cast into complex shapes by pouring of liquid steel into a mould in which it sets to the required shape. Casting defects. It mainly involves four basic steps. Physical methods for descaling include use of wire brushes, extra blows, scraping devices, polishing or blasting. Cold-pressure welding is accomplished by the application of high pressure at room temperature; forge welding (forging) is done by means of hammering, with the addition of heat. Recent Examples on the Web The basic principles, and the metallurgy, were proved to be fine. Softening A process used to soften metals through annealing or tempering. — J. I. The process of hydrometallurgical leaching is multi-step: Extract the metals from the ores with a liquid (water, acid, base, or a salt solution). Descaling is a process of removing oxide deposits from a heated stock, either before or during forging operations. Powder Metallurgy is can be defined as the process of preparation and process the powdered iron and nonferrous metals are called as powder metallurgy.. Powder Metallurgy Process: These factors make this process most suitable for mass production. THIS GLOSSARY contains the definitions of some 3500 technical terms encountered in the metallurgical literature. See more. Metallurgy - Metallurgy - Physical metallurgy: Physical metallurgy is the science of making useful products out of metals. Casting is a forming process which converts liquid steel into a solid product. Reduction by Electrolysis Reduction of highly electropositive (reactive) metals like K, Na, Ca, Mg, Al oxides/halides. Metal parts can be made in a variety of ways, depending on the shape, properties, and cost desired in the finished product. You may also come across it in other cases such as one method of extracting copper and in the purification of copper. process for joining separate pieces of metal in a continuous metallic bond. This is a common extraction process for the more reactive metals - for example, for aluminum and metals above it in the electrochemical series. The desired properties may be electrical, mechanical, magnetic, or chemical in nature; all of them can be enhanced by alloying and heat treatment. Metallurgy definition is - the science and technology of metals. A metallurgical thermal process in which a metal is separated in fused form from nonmetallic materials, or other undesired metals with which it is associated. History of metallurgy. Fig 1 Metallurgical processes and steel product defects. The process of removing oxygen from a metallic oxide so as to convert it (metallic oxide) into a metal is known as reduction or smelting. The present-day use of metals is the culmination of a long path of development extending over approximately 6,500 years. Metallurgy definition, the technique or science of working or heating metals so as to give them certain desired shapes or properties. A process metallurgist must be an expert in various metallurgical processes used to shape metals and alloys as required by the employer.