Brief introduction to the quality of spring steel bar materials

The effect of size and size In the 25 complaints of unexplained fracture failure, most of them focused on large-size wire rods ><11mm, indicating significant dimensional effects. The large-size wire rod processing state is hard, the uniformity of the structure and the proportion of the sorbite body are low, so that the internal stress and the relative brittleness are large, and the drawing and winding stress required for the drawing and the winding spring deformation are large. It is easy to reach the tensile limit of the material and break. For large specifications, it can be directly cold deformed, depending on the overall quality performance of the material. However, it is certain that the larger the specification, the lower the cold plastic deformation ability and the greater the fracture sensitivity, so it needs to be strictly controlled in production. According to the usage and complaints of most customers, the current specifications can be directly cold-drawn springs under <14mm, but it is necessary to ensure proper organization and internal stress, and >14mm, it is recommended that users use annealing or heat. Forming around. The influence of surface quality on the surface of severe cracks, bumps, folds and other defects, their existence must be the origin of the material failure, easily lead to material fracture.

The management of the cause of the complaint analyzes the quality of the problem. The multiple problems occur repeatedly and no effective improvement and preventive measures are taken. This indicates that there are problems in management. Quality experts believe that 80% of the quality problems are caused by poor management, the quality of the company is not ideal, reflected in the lack of research and attention to users, lack of long-term clear quality strategy plans and goals, leadership attention to quality and understanding, The lack of quality knowledge and skills of employees, the general lack of quality awareness, and the light weight of production and quality are all important reasons for the low quality of products. Only by managing quality, will the bottleneck of quality improvement be fundamentally solved. power. User complaints are mostly common defects, not only related to the company's process equipment, process control and management, but also insufficient research on user requirements.