1, macro test
The chemical composition is crucial to ensure the performance of the steel. However, the composition is qualified and can not fully explain the properties of the steel. Due to the inhomogeneity of the internal structure and composition of the steel, the macro-inspection largely complements the deficiencies in this respect.
Macro inspection can observe the crystallization of steel, the continuity of the steel damage and the non-uniformity of some components.
Standard "low magnification structural steel structural defect rating" GB1979
Common macro 8 kinds of defects: segregation, loose, inclusions, shrinkage, bubbles, white spots, cracks, folding.
2.1, the assessment of the annealing organization
The purpose of the anneal is to reduce the hardness of the steel for ease of machining and also to prepare for the subsequent heat treatment.
Carbon tool steel annealing organization according to the first level of GB1298 rating chart assessment.
2.2, carbide heterogeneity
Cr12-type ledeburite steel, the organization contains a large number of eutectic carbides, carbides unevenness on the use of performance have a very important impact, so the distribution of its carbide must be strictly controlled.
All in all, the mold manufacturing plant and workshop production object is more cumbersome, and how many one-piece, small batch, so as to mold production quota formulation and management of a certain degree of difficulty, coupled with the plant and workshop production methods, Equipment, technical quality is not the same, so in the development of quotas, we must find out the appropriate method according to the actual situation of the factory and the workshop to develop both advanced and reasonable working hours fixed, in order to improve labor productivity purposes.