Technological progress promotes fastener innovation - new material application is effective

Core Tip: On the one hand, the development of fastener technology, tools and equipment, etc. to a large extent, to the material technology, especially to improve the plasticity of the material level of technology and progress as a transfer. On the other hand, fastener product design, research and development is also to a considerable extent by the influence of materials. Such as the fastener structure, form, precision, performance and other constraints.

Since the 21st century, with the rapid development of microelectronics and computer technology, bioengineering technology, aerospace technology and many other technologies, causing a new wave of technological revolution. Fasteners, which are one of the most influential basic parts of the machinery manufacturing industry, have put forward new and higher requirements in terms of performance, function and especially safety.

　　As we all know, process and material, as the basis of fastener manufacturing, play a vital role in the quality and performance of the product.

　　In the long term future, fasteners are still based on steel as the mainstream material, based on the characteristics of steel materials and along with technological advances, the rapid development of the iron and steel industry to promote the enhancement of fastener plastic molding technology, in line with the requirements of modern fastener products and processes of iron and steel materials, for today's fasteners in the country's annual output of more than 4.5 million tons of the huge scale of production, to provide an important guarantee.

　　On the one hand, the development of fastener technology, tools and equipment, etc. to a large extent, to the material technology, especially to improve the plasticity of the material for the transfer of the technical level and progress. On the other hand, fastener product design, research and development is also to a considerable extent by the influence of materials. Such as the fastener structure, form, precision, performance and other constraints.

　　In order to adapt to the needs of the structural connection, new technological advances in the iron and steel industry continue to introduce new materials with superior performance. Beijing Iron and Steel Institute as the relying unit of China's “973” program, “a new generation of iron and steel materials,” the application of the results of the ADF series of delayed fracture-resistant high-strength steel research was successful, with ultra-fine grain, ultra-cleanliness, high uniformity, cost-effective and more reasonable. Reasonable, can be manufactured 13.9 grade and 14.9 grade high strength bolts, and has entered industrial applications and mass production.

　　In order to meet the special conditions or special specifications, the need for fasteners connected to the special environmental conditions, due to a variety of objective reasons, titanium alloy fasteners in the aerospace demand is still growing dramatically. tb3, tb5, tc4 and tc16 titanium alloy fasteners such as the use of a large number of to ensure that the technical and economic characteristics of the aircraft.

　　For the engine class of high-strength fasteners require higher and more uniform quality and longer service life, the development of a new 30CrNi4MoA special steel for marine medium-speed diesel engine connecting rod bolts, cylinder head bolts are not removable connection, the service life of 30,000-50,000 hours or more. From reducing the manufacturing and installation process of environmental pollution and reduce the dependence on resources to protect the environment on which mankind depends for survival, people on the one hand, the fastener manufacturing process of pollution, such as noise, smoke, wastewater pollution, etc. have put forward a strong demand for improvement; on the other hand, through the reduction of hazardous substances in the iron and steel materials and improve the composition of steel, improve the rolling process to reduce the pollution of the environment. Such as the production of cold-worked strengthened non-quenched steel without heat treatment. There are MFT8 non-quenched steel produced by Maanshan Iron and Steel; FM08MnSi, FM08MnSiV non-quenched steel fasteners produced by Baosteel have been successfully applied to all kinds of components.

　　Mn - V - B cold heading steel development, below M20 can guarantee access to martensitic organization, can be used to replace the medium-carbon alloy steel tempering heat treatment. 20MnVB steel production CA488 engine connecting rod bolts, static strength than the 40Cr steel bolts to improve the 30% - 35%, bolts to increase the load-bearing capacity of 40% - 45%, to achieve the best strength and toughness of the best match.

　　20Mn2V, SWRCH22A and 20Mn steel is used in a large number of automobiles, motorcycles and other vehicles spot welded bolts, nuts, it is strengthened by the high-temperature low carbon martensite, good strength and toughness match, to avoid defects in the medium-carbon steel is prone to, the performance of the steel is equivalent to or better than SWRCH45K, SWRCH35K.

　　In short, in recent years, the progress of alloying technology in steel materials to meet the needs of fastener manufacturing.