Lubrication of metal stamping parts is crucial for reducing die wear and improving surface quality. The key lies in the strategic selection of lubrication methods and materials to form a stable lubricating film between the die and workpiece, thereby reducing friction, distributing stress, and preventing metal adhesion. While traditional oil-based lubricants can meet basic requirements, they pose challenges such as residual oil, difficulty cleaning, and environmental pollution. Modern processes favor efficient and environmentally friendly lubrication solutions, with fine-blanking oil and water-based lubricants being particularly widely used.
Fine-blanking oil serves multiple purposes in metal stamping parts processing. It lubricates the die surface, reducing friction and wear between the metal and the die. It provides a smooth contact surface, allowing the metal to pass smoothly through the die and minimizing the risk of deformation or damage caused by friction. Fine-blanking oil also reduces stamping force and energy consumption, improving stamping efficiency and quality by reducing friction between the metal, the punch, and the die. Furthermore, it forms a protective film that protects the metal from oxygen and moisture, reducing the risk of oxidation and corrosion, and extending the service life of stamped parts. In terms of surface quality improvement, fine stamping oil can reduce defects such as scratches, burrs, and cracks, resulting in a smoother, finer surface finish on stamped parts, enhancing product appearance and quality.
Water-based lubricants are increasingly becoming the mainstream choice for lubricating metal stamping parts due to their environmentally friendly nature. Compared to oil-based lubricants, water-based lubricants offer advantages such as no flash point, easy cleaning, and reduced waste oil emissions. Furthermore, water-based lubricants can reduce usage by 50% and waste oil emissions by 75%. Their high penetrating properties ensure that the lubricant quickly covers the contact surface between the die and the workpiece, forming a uniform lubricating film that effectively reduces friction and wear. Furthermore, water-based lubricants improve compatibility with welding and spraying processes, reducing problems such as cold welds and porosity in subsequent processes, and improving overall product quality. For example, in automotive panel stamping, the use of water-based lubricants simplifies cleaning processes, reduces waste oil disposal costs, and promotes the transition of stamping processes toward green manufacturing.
Lubricant selection requires differentiation based on the specific metal material and stamping process requirements. For materials prone to adhesion, such as high-strength steel, lubricants with stronger pressure and temperature resistance are required to prevent die wear caused by lubricating film failure. Furthermore, the higher hardness of tool materials during high-strength steel forming places even stricter demands on the lubricant's anti-friction and anti-stick properties. This requires optimizing the lubricant formulation to enhance its adhesion and toughness. For materials like stainless steel, a pure water-based lubricant can be used. Its unique combination of additives creates a tough lubricating film, preventing defects such as cracks and wrinkles.
Mold design has a crucial impact on lubrication effectiveness. Optimizing the mold structure can enhance lubricant storage and supply capacity, ensuring lubricant film stability. For example, chamfering the inner side of the blank holder and the outer side of the counter-pressure plate, or maintaining a large gap between the ejector pin and the punching die, increases lubricant storage space and prevents lubricant from being displaced during fine blanking. Furthermore, using a sunken stepped surface on the outer side of the blank holder and die working area prevents lubricant from being displaced from the strip, potentially impacting lubrication during subsequent stamping.
Refined control of the lubrication process is key to improving the quality of metal stamping parts. Optimizing lubrication parameters through simulation tools can find the balance between reducing friction and preventing excessive material flow. For example, in automotive panel stamping, simulation software with friction models can simulate material deformation behavior under different lubrication levels, thereby determining the optimal lubrication strategy. Furthermore, regular lubricant filtration to prevent impurities can avoid increased surface roughness caused by poor lubricant quality, thereby improving stamping accuracy and quality.
Balancing environmental protection and efficiency is a key development direction for lubrication processes in metal stamping parts. With increasingly stringent environmental regulations, the industry is gradually phasing out highly polluting oil-based lubricants and turning to environmentally friendly options such as water-based and synthetic lubricants. These new lubricants not only meet performance requirements but also simplify cleaning processes and reduce waste oil disposal costs, driving the stamping process towards green manufacturing. In the future, with continuous advancements in materials science and lubrication technology, lubrication processes for metal stamping parts will become even more efficient and environmentally friendly, providing strong support for the sustainable development of the manufacturing industry.
