Analysis and control methods for common defects in precision casting molds

Precision casting molds are important tools for producing high-precision and high-quality castings. However, various defects such as cracks, bubbles, internal deformation, etc. often occur during the mold manufacturing process, which affect the service life of the mold and the quality of the casting. Therefore, the analysis and control of mold defects is an important part of manufacturing precision casting molds. This article will introduce the analysis and control methods of common defects in precision casting molds.

1、 Classification of mold defects

Surface defects: Refers to defects on the surface of a mold, such as pores, cracks, scratches, etc.

Geometric defects: Refers to defects with irregular internal or external shapes and inaccurate dimensions in the mold.

Material defects refer to defects such as non-uniformity, foreign objects, and inclusions in the mold.

2、 Analysis method of mould defect

Visual inspection method: Observe the surface and interior of the mold for defects with the naked eye or magnifying glass.

X-ray inspection method: By irradiating the mold with X-rays and observing whether there are cracks, pores, etc. inside the mold, the internal structure of the mold can be visually displayed.

Sound wave detection method: Detect internal defects of the mold through sound waves, ultrasonic waves, etc.

Metallographic inspection method: Use a metallographic microscope to inspect the material structure of mold products to discover material defects.

Heat treatment detection method: By conducting heat treatment on the mold, observe the changes in the material structure after heat treatment to discover material defects.

3、 Control method of mould defect

Formulation of technical requirements: In the process of manufacturing molds, corresponding technical requirements should be formulated based on the required accuracy and quality to ensure the production of molds that meet the requirements.

Material selection and treatment: Materials with good quality, no impurities, uniform composition, and fine structure should be selected to avoid defects such as inclusions and bubbles. At the same time, the material should be subjected to processing such as heating, forging, quenching, and tempering to improve its performance and fatigue resistance.

Reasonableness of design: When designing molds, it is necessary to minimize overly complex structures, reduce machining difficulty, and reasonably set exhaust holes and flow channels to fully discharge gas in the castings, avoiding the occurrence of pores and defects inside the castings.

Strict control of production process: During the mold manufacturing process, each process link should be strictly controlled to control processing errors, material residues, and other situations to ensure the accuracy and quality of the mold. At the same time, operating procedures should be followed to ensure standardized operation.

Completeness of testing: Comprehensive testing should be conducted on the products of the mold, including surface inspection, X-ray testing, acoustic testing, metallographic testing, heat treatment testing, etc., as well as pre factory testing and mold testing to discover and correct defects.