Core knowledge of the steel fine-thread phosphating screw industry development

Steel fine-thread phosphating-treated screws, as a core product in the field of metal fasteners, leverage the precise characteristics of fine-thread design and the protective advantages of phosphating treatment, and are widely used in key areas such as high-end manufacturing, new energy, aerospace, etc. In the recent period, driven by the promotion of standard improvement, process upgrading, and market integration, they have gradually entered a new stage of high-quality development, becoming an important lever for the structural upgrading of the fastener industry.
The combination of fine-thread and phosphating treatment is the core competitiveness of this product. Compared with ordinary coarse-thread screws, fine-thread screws have smaller pitch and thinner tooth profile, featuring strong self-locking ability, uniform stress distribution, and high connection accuracy. They can be adapted to vibration conditions and precision assembly scenarios, effectively preventing connection loosening. Phosphating treatment, through chemical transformation reactions, forms a 2–8 μm porous phosphate crystal film on the surface of steel screws, which can not only enhance the adhesion of subsequent coatings but also stabilize the torque coefficient, avoid hydrogen embrittlement risks, perfectly meet the strict requirements of fine-thread for dimensional accuracy, and significantly enhance the corrosion resistance and wear resistance of the screws.
The improvement of industry standards is an important support for the enhancement of product quality. Currently, the industry follows the GB/T 5786-2016 standard for "Hexagon Head Bolts - Fine Thread - Full Thread", which adopts the international ISO standard. This standard has refined the size tolerances, thread accuracy, mechanical properties, etc. of the screws. Compared to the previous version, it has reduced the tolerance range of the head thickness and the diameter of the shaft, added fatigue strength requirements, and provided a unified basis for production and inspection. It is reported that the ISO1891 digital thread detection standard to be implemented in 2026 will also promote enterprises to upgrade their detection equipment, further enhancing the level of product precision control.
Process iteration and environmental transformation are the core trends in the industry's development in the recent period. The traditional high-energy consumption and high-pollution zinc-based phosphating process has been gradually replaced by normal-temperature rapid zinc-based, low-nickel-manganese-based, and nano-composite phosphating processes. Some high-end scenarios have piloted the application of zirconium-titanium-based and silane-based phosphorus-free conversion technologies, which not only ensure a 72–120-hour salt spray protection performance but also significantly reduce wastewater discharge and energy consumption, meeting domestic and international environmental protection regulations such as RoHS and REACH. At the same time, the popularization of digital equipment such as online film thickness monitoring and intelligent temperature control has achieved precise control of phosphating process parameters, promoting the product yield rate to over 99%.
The market shows a dual characteristic of structural growth and increased industry concentration. The demand for high-end fields such as electric drives for new energy vehicles, battery packs, and photovoltaic and wind power equipment has surged, driving up the demand for high-strength steel fine-thread phosphating screws. Since 2025, the proportion of high-strength and surface treatment upgraded products has reached 28.4%. Industry consolidation has accelerated, with the combined market share of the top ten enterprises having risen to 39.7%. Leading companies such as AVIC Jingong and Jin Yi Industrial have achieved full-process automated production lines, while small and medium-sized manufacturers have gradually been eliminated from the market due to environmental protection investment and technological upgrading pressures.
Currently, the steel fine-thread phosphating treatment screws industry is in a critical period of transitioning from scale expansion to quality and efficiency improvement. With stricter standards, environmental protection requirements, and upgraded demand, these factors have become the main driving forces for industry development. In the future, as the domesticization of high-end manufacturing accelerates and digital processing techniques become more widespread, enterprises will further focus on enhancing the accuracy of threads, the performance of the coating layer, and the ability for full lifecycle traceability. This will drive the products to upgrade towards higher strength, greater environmental friendliness, and greater precision, continuously unleashing the development potential in specialized fields.