（自己参考内容自行创作）
The national standard GB2277-87 Silicon Iron was formulated by the State Bureau of Quality and Technical Supervision (now the General Administration of Quality Supervision, Inspection and Quarantine) in October 1987 and promulgated on January 8, 1988. The implementation date of the standard is October 1, 1988. The implementation of this standard is intended to better serve and protect the production of products from silica iron and the interests of consumers.
Silicon Iron (commonly referred to as Silico-Iron) is a popular form of iron with a high silicon content, usually between 10 and 15%. It is created by combining iron ore with other minerals and elements, including silicon, in a high temperature electric arc furnace. The resulting material is much harder and stronger than pure iron, and is thus well suited for structural building materials and automotive parts.
The national standard GB2277-87 Silicon Iron stipulates the requirements and test methods for silico iron products produced in China. It involves the classification, performance requirements and test methods of silico iron. It has guiding significance for the production and application of silico iron products in the country.
The standard stipulates three types of silico iron products according to the silicon content ratio and temperature mark: carbon-silicon alloy cast iron (the maximum silicon content is 3.85%), medium-carbon silicon-magnesium alloy cast iron (the maximum silicon content is 4.85%), and high-carbon silicon-magnesium-molybdenum-bearing alloy cast iron (the maximum silicon content is 5.85%).
In terms of performance requirements, the standard stipulates that the allowable deviation of chemical composition of cast iron shall be in accordance with the corresponding standard GB/T222-84, and the surface shrinkage of cast iron shall not exceed the size required by relevant national standards. It also stipulates the requirements for hardness of different types of silico iron and its fatigue strength.
The test method stipulated by the standard includes chemical composition determination method, carbon content content determination method, microstructure determination method, structural determination method, embrittlement determination method and other items.
The national standard GB2277-87 Silicon Iron is an important part of Chinas product standards system and has important guiding significance for the production, use and quality control of steel products in China. It has important reference value for the production, use and product quality control of silico iron products in China.
