What die-casting process can be used to ensure that the zinc alloy material meets the standards for density and mechanical strength?
Release Time : 2026-02-03
Alloy dog buckles, widely used connectors in hardware accessories, rely on the density and mechanical strength of zinc alloy for their core function. In die casting, ensuring alloy dog buckles meet industry standards requires comprehensive optimization across mold design, die casting parameter control, material pretreatment, and post-treatment, forming a complete process system. The following analysis focuses on key process steps, exploring how systematic control can achieve product performance standards.
Mold design is the cornerstone of the die casting process, directly impacting the molding quality of alloy dog buckles. Given the good fluidity but high shrinkage rate of zinc alloys, the mold must employ a stepped parting surface design, using a multi-stage core-pulling mechanism to reduce the risk of mold misalignment and prevent flash. Simultaneously, the gating system needs to be optimized into a "fan-shaped + diverting cone" structure to ensure the molten metal fills the cavity in a laminar flow state, reducing internal defects caused by turbulent air entrapment. Furthermore, fine venting grooves should be installed at the end of the mold cavity, combined with spiral cooling channels, to control mold temperature fluctuations within a reasonable range, preventing cracks or deformation caused by thermal stress concentration. Precise control of die-casting parameters is crucial for ensuring high density. During the injection stage, a multi-stage injection curve of "slow-fast-slow" is employed: the initial slow injection stage uses low-speed filling to avoid air entrapment; subsequent rapid injection ensures the molten metal completely fills the cavity before solidification; and the final pressurization stage uses high pressure to maintain the molten metal's shrinkage and eliminate internal shrinkage cavities. The holding time needs to be dynamically adjusted according to the part's wall thickness to ensure sufficient shrinkage compensation while avoiding overpressure that could lead to mold wear or flash thickening. The cooling stage combines mold water channels with air cooling to ensure uniform cooling of the casting and prevent localized overheating that could cause grain coarsening or residual stress.
Material pretreatment is a fundamental guarantee for improving mechanical strength. Zinc alloy raw materials require strict smelting, impurity removal, and temperature control: During smelting, refining agents are added to break down the oxide layer, and stirring promotes the flotation of inclusions; in the impurity removal stage, ceramic filter plates are used to filter the molten metal, combined with rotary degassing technology to reduce hydrogen content and avoid porosity defects; temperature control requires stabilizing the molten metal within a suitable range to prevent overheating leading to coarse grains or undercooling causing insufficient fluidity. Furthermore, the raw material composition must strictly comply with standards to avoid segregation of elements such as aluminum and copper that could affect material properties.
Post-processing is crucial for optimizing product performance. The deburring stage requires a combination of vibratory grinding and ultrasonic cleaning to thoroughly remove flash and residual abrasive from the parting surface and deep cavities, preventing surface scratches; surface treatment requires selection of polishing, electroplating, or spraying processes depending on the application scenario. Electrochemical polishing can remove the surface oxide layer and improve corrosion resistance, while environmentally friendly electroplating processes can meet the salt spray test requirements of export standards. For high-load parts, aging treatment can eliminate internal stress, significantly improve tensile strength and elongation, and ensure long-term reliability.
A robust quality control system is crucial for process stability. By real-time monitoring of parameters such as injection pressure and mold temperature using the Industrial Internet of Things (IIoT), combined with AI algorithms to predict defects, adaptive adjustments to process parameters can be achieved, keeping the defect rate extremely low. Simultaneously, random inspections of castings using X-ray flaw detection and metallographic analysis can promptly identify internal defects such as porosity and shrinkage cavities, providing data support for process optimization. Furthermore, a strict supplier management system ensures that raw material composition and smelting processes meet standards, eliminating performance fluctuations at the source.
The die-casting process for alloy dog buckles requires systematic optimization through mold design, parameter control, material pretreatment, post-treatment, and quality control to ensure the zinc alloy material meets density and mechanical strength standards. With the promotion of intelligent die-casting technology and environmentally friendly processes, future alloy dog buckle production will place greater emphasis on process stability and sustainability. Deep integration of IIoT and AI technologies will enable precise control throughout the entire process from raw materials to finished products, providing higher-performance connectivity solutions for pet supplies, bag accessories, and other fields.