Bubble holes appear in the product after sintering

Larger isolated bubble-shaped holes appear inside the product. This defect is usually found after demolding of the product or during cross-section inspection, and is mostly concentrated in thick-wall areas or at the end of resin flow. Internal defects reduce the mechanical strength and compactness of the product, and have a particularly serious impact on products with pressure-bearing and sealing requirements.

(1) Temperature parameter aspect: Low-boiling impurities or moisture mixed into the powder vaporize and expand at the sintering temperature, causing insufficient reaction kinetics or deterioration of material flowability, affecting the normal progress of the '2079851475616104453. (2) Process factor: Large bubbles are entrapped during preforming; this factor affects the '2079851475616104453 and final quality of the product. (3) Material aspect: The volatile content or moisture in the raw material exceeds the standard, vaporizing at the molding temperature to form a bubble source. (4) Process aspect: Air is entrained during the filling or pouring process, and the venting/degassing measures are insufficient. (5) Mold aspect: The cavity venting structure design is unreasonable, and gas cannot be effectively discharged.

(1) Material selection: Fully dry the raw material before use, establish material selection evaluation standards, and determine the optimal plan through comparative tests. (2) Process strengthening: Vacuum degassing during the preforming process, increase the vacuum degree and ensure sufficient treatment time, and proceed to the next process only after confirming that the bubbles are completely eliminated. (3) Parameter adjustment: Increase the preforming pressure to compact and discharge air., it needs to be evaluated in combination with equipment capacity, gradually increase the pressure and check the compactness and dimensional changes of the product. (4) Preventive measure: Establish standardized degassing and casting operation procedures, regularly train operators, and inspect the first piece of each shift to confirm that there are no bubble defects.

The essence of this problem is that the gas is not effectively removed during the sintering '2079851475616104453, and it needs to be solved collaboratively from three aspects: degassing process, casting method, and venting design.