，
Article: Application of Pig Iron for Castings
Pig iron is a type of ferrous metal alloyed from iron ore which is used as an intermediate material in the production of tempered and end-use metal products such as castings. Pig iron contains between 4.5 and 5.5 percent carbon, between 1.0 and 1.2% silicon, and between 0.1 and 0.3% sulfur, making it an ideal material for casting. The castable nature of pig iron makes it invaluable for foundries in producing a variety of items with complex shapes and varied dimensions. Pig iron is also extremely wear resistant, making it useful for the production of machine parts, tools, and structural components such as belts, couplings, and frames.
The YB/T14-1991 standard is the Chinese national standard for the application of pig iron in the foundry, and it outlines proposed design requirements, castability characteristics, and quality control guidelines for the production of castings. According to the standard, pig iron is most suitable for the casting of automotive, transmission, and power train components. In general, the requirements for casting with pig iron ensure that the materials used produce a uniform, homogenous microstructure with a low probability of shrinkage defects, inclusions, or gas porosity in the casting. Without the proper measures and quality control, poor castings may result in reduced part functionality and life and increased scrap rates.
The YB/T14-1991 standard specifies requirements for both the raw material pig iron and the castings. For the raw material pig iron, carbon and sulfur content must meet requirements, with silicon content in most cases needing to be no higher than 1.2%. For ferrous castings made from pig iron, the standard calls for a melting temperature ranging from 1,450 to 1,500 °C, with the standard shrinkage rate laid out in the document. In terms of quality control, the document states that casting production should be monitored for changes in chemical composition, temperature, and microstructure. Particular care should be taken to ensure that the casting is free of defects or imperfections.
In conclusion, the use of pig iron for castings is a essential and reliable practice specified in the YB/T14-1991 Standard. This standard outlines the proposed design requirements and castability characteristics that must be adhered to in order to maximize the performance and life of the parts and minimize scrap rates. Through proper quality control and design, castings made with pig iron can be reliably produced with consistent quality.
