Engineering plastic products mold processing how to reduce defects

1, reasonable use of cooling lubricant, cooling, washing, lubrication of the three major roles, to maintain clean cooling lubrication, so as to control the grinding heat within the allowable range, in order to prevent the thermal deformation of the workpiece. Improve the cooling condition during grinding, such as adopting measures such as oil-sand immersion wheel or internal cooling wheel. By introducing cutting fluid into the center of the grinding wheel, cutting fluid can directly enter the grinding area and play an effective cooling role to prevent surface burns of the workpiece.
2, the quenching stress after heat treatment is reduced to the minimum, because the quenching stress, network carbonized structure under the action of grinding force, the phase change of the structure is easy to make the workpiece crack. In order to eliminate the residual stress of high precision die grinding, low temperature aging treatment should be carried out after grinding to improve the toughness.
3, eliminate grinding stress can also will die in 260 ~ 315 ℃ of salt bath at 1.5 min, and then in 30 ℃ oil cooling, so can drop 1 HRC hardness, residual stress reduced by 40% ~ 65%.
4. For precision grinding of precision molds with dimensional tolerance within 0.01mm, the influence of ambient temperature shall be paid attention to, and constant temperature grinding shall be required. By calculating, the 300 mm long steel, temperature 3 ℃, the change of the material there are about 10.8 microns, (10.8 = 1.2 * 3 * 3, 1.2 mu per 100 mm deformation m / ℃), various finishing processes are required to fully consider the influence of this factor.
5. Electrolytic grinding is adopted to improve mold manufacturing precision and surface quality. Electrolytic grinding, grinding wheel scraping oxide film: rather than grinding metal, so the grinding force is small, grinding heat is small, will not produce burr, crack, burn phenomenon, general surface roughness can be better than Ra0.16 m; In addition, the grinding wheel wear small, such as grinding hard alloy, silicon carbide grinding wheel wear is about the weight of the hard alloy grinding off 400% ~ 600%, with electrolytic grinding, grinding wheel wear only hard alloy wear off the amount of 50% ~ 100%.