3. The surface of the mold heat treatment to strengthen the quality and impact on life
Mold heat treatment the nature and quality of life of the mold a great impact. Practice shows that the die parts of the quenching distortion and cracking, early fracture during use, while the metallurgical and materials quality, forging quality, mold structure and process related, but related more to die of heat treatment. According to statistical analysis of failure causes of mold, heat treatment failure due to improper accounting for more than 50%. Practice shows that the mold material must be accompanied by high heat treatment process properly, can really play a material's potential. Parts surface hardening mold work purpose is to obtain the effect of external hard tough inside, so be hardness, wear resistance, toughness, good resistance to fatigue with. Many ways to die surface hardening, surface treatment technology of new technologies developed rapidly. In addition to Nitrocarburizing and ion nitride, boride, seepage niobium, vanadium permeability, hard chrome plated and spark strengthening, the chemical vapor deposition (CVD) and physical vapor deposition (PVD) has been gradually adopted. By CVD and PVD treatment, the mold surface covered with super-hard material, such as TiC, TiN, etc.. High hardness, wear resistance, corrosion resistance, adhesion is very good, can improve the die life several times to several times.
4. Manufacturing precision of the die parts of die life
Precision die manufacturing and life in it in particular, mold surface roughness on the mold a great impact. If using Crl2MoV steel blanking die, if the surface roughness value R = 1.6 m, its life span is about 30,000. Such as polished by the precision, surface roughness value R = 0.4 m, life can be increased to 4-5 million. Therefore, the working parts of the mold surface, the general must go through grinding, grinding, polishing and other finishing and fine processing.
5. Other aspects of the impact of die life
(1) Press the accuracy is not high, but also easy to make die damage.
(2) die in the press or not installed properly and the operator's technical level, on the tool life is also greatly affected.
(3) dies in the custody and maintenance of good and bad, and the use of lubricant condition also affects mold life.
6. Conclusion
In actual production, sheet metal dies for use, rare case of non-normal wear and tear. But when the die plate was found prone to irregular wear, we always study for the problems summarized. Because of a cold die, from the design, manufacture, assembly, commissioning and installation and use, all spent many hours, while the convex die, die material used, mostly high-quality alloy steel. Therefore, the die cost is relatively high. Therefore, in the production of understanding the factors that affect the die life and take the appropriate measures to guide the production of great practical significance.
References
1. Wang KK (1980) System approach to injection molding process. Polym-Plast Technol Eng 14(1):75–93.
2. Shelesh-Nezhad K, Siores E (1997) Intelligent system for plastic injection molding process design. J Mater Process Technol 63(1–3):458–462.
3. Aluru R, Keefe M, Advani S (2001) Simulation of injection molding into rapid-prototyped molds. Rapid Prototyping J 7(1):42–51.
4. Shen SF (1984) Simulation of polymeric flows in the injection molding process. Int J Numer Methods Fluids 4(2):171–184.
5. Agassant JF, Alles H, Philipon S, Vincent M (1988) Experimental and theoretical study of the injection molding of thermoplastic materials. Polym Eng Sci 28(7):460–468.
6. Chiang HH, Hieber CA, Wang KK (1991) A unified simulation of the filling and post-filling stages in injection molding. Part I: formulation. Polym Eng Sci 31(2):116–124.
7. Zhou H, Li D (2001) A numerical simulation of the filling stage in injection molding based on a surface model. Adv Polym Technol 20(2):125–131. 冷冲模具使用寿命的影响及对策英文文献和中文翻译(5):http://www.youerw.com/fanyi/lunwen_8014.html