| Quality Management System | A documented quality management system certified to ISO 9001:2015, with controlled procedures for design review, production, inspection, nonconformity handling, and corrective action. | Valid certificate, certification scope, issuing body, audit status, and recent corrective-action records. | Shows whether quality control is systematic and repeatable rather than dependent on individual operators. | High |
| Alloy Identification and Traceability | Each production lot should be traceable to the alloy grade, melting batch, supplier material certificate, and date of manufacture. | Material certificates, batch labels, furnace records, and traceability samples from raw material to shipment. | Prevents material mix-ups and supports investigation if a casting fails in service. | High |
| Applicable Casting Standard | Product requirements should be defined with recognized casting specifications such as ASTM B86 where applicable, together with customer drawings and acceptance criteria. | Inspection standard, alloy specification, approved drawings, control plan, and sample inspection report. | Creates an objective basis for evaluating material, workmanship, and acceptance decisions. | High |
| Dimensional Accuracy | Critical dimensions should be controlled according to the approved drawing and agreed casting tolerances. General tolerances may reference ISO 8062-3 when suitable for the design. | First-article inspection report, calibrated CMM or measuring equipment records, and capability data for critical dimensions. | Accurate dimensions are essential for assembly fit, sealing, movement, and interchangeability. | High |
| Process Capability | For stable, mature processes, critical characteristics should commonly demonstrate a Cpk of at least 1.33, unless a different customer requirement is agreed. | Control charts, capability studies, sample size, measurement method, and definition of critical characteristics. | Capability data indicates whether the process can consistently meet specifications, not just pass one inspection. | High |
| Internal Casting Quality | Castings should be free from unacceptable porosity, cracks, cold shuts, inclusions, flash, and short shots according to the approved defect limit. | Visual inspection standard, sectioned samples, X-ray or CT results when required, and defect classification records. | Internal defects can reduce strength, cause leakage, affect machining, or lead to premature failure. | High |
| Mechanical Properties | Tensile strength, yield strength, elongation, and hardness should be verified against the specified alloy grade and applicable standard. | Independent or in-house laboratory reports, test methods, specimen details, and lot identification. | Confirms that the selected alloy and process provide the required functional performance. | High |
| Surface Finish and Appearance | Surface requirements should define acceptable limits for flow marks, sink marks, scratches, stains, burrs, flash, and polishing or plating defects. | Approved golden sample, visual limit samples, surface roughness results, and finishing inspection records. | Consistent appearance protects product quality and reduces disputes caused by subjective acceptance. | Medium |
| Tooling and Mold Control | Tool design should include appropriate draft, gating, overflow, venting, cooling, and maintenance provisions for zinc alloy die casting. | Mold-flow review, tool drawings, preventive maintenance plan, tool-life records, and repair history. | Well-controlled tooling improves filling, reduces defects, and maintains dimensional stability over production runs. | High |
| Equipment and Calibration | Die-casting machines, furnaces, testing instruments, and dimensional equipment should be maintained and calibrated at defined intervals. | Equipment maintenance logs, calibration certificates, calibration status labels, and out-of-tolerance action records. | Reliable equipment and measurement systems reduce process variation and inaccurate inspection results. | High |
| Secondary Operations | Trimming, deburring, machining, drilling, tapping, polishing, and assembly should have documented work instructions and inspection points. | Operation flow chart, work instructions, tool-life records, gauge records, and inspection reports for finished features. | Many casting failures occur after molding because secondary operations can damage critical surfaces or dimensions. | High |
| Surface Treatment Compliance | Plating, painting, powder coating, passivation, or other finishes should meet the agreed thickness, adhesion, corrosion, color, and appearance requirements. | Coating thickness results, adhesion tests, corrosion test reports when specified, color records, and approved process parameters. | Surface treatment affects corrosion resistance, appearance, wear resistance, and product life. | Medium |
| Restricted Substances | Materials and finishes should comply with applicable requirements such as RoHS Directive 2011/65/EU and REACH Regulation (EC) No. 1907/2006 when required by the destination market. | Material declarations, supplier declarations, laboratory test reports, and updated chemical compliance records. | Supports legal market access and reduces environmental and chemical compliance risks. | High |
| Inspection Planning | A documented control plan should identify incoming, in-process, final, and pre-shipment inspections, including sampling frequency and reaction plans. | Process flow chart, control plan, inspection standards, sampling plan, and nonconforming-product procedure. | Ensures that important characteristics are checked at the correct stage of production. | High |
| First Article Approval | Before mass production, the supplier should submit samples that represent the final tooling, material, process, finishing, and inspection method. | First-article inspection report, dimensional results, material report, functional test results, and approved sample record. | Confirms that the complete production process meets requirements before larger quantities are released. | High |
| Nonconformance and Corrective Action | Quality issues should be documented using root-cause analysis and corrective-action methods such as 8D, with effectiveness verification. | Recent 8D reports, containment records, root-cause analysis, corrective-action deadlines, and verification evidence. | Shows how effectively the supplier prevents recurring defects instead of only replacing rejected parts. | High |
| Packaging and Shipment Protection | Packaging should prevent scratches, deformation, corrosion, contamination, and mixing of part numbers during storage and transport. | Packaging specification, drop or transport evaluation when needed, labeling examples, and shipment inspection records. | Good parts can become unacceptable through poor handling or inadequate protection after final inspection. | Medium |
| Delivery Reliability | The supplier should maintain documented production planning, capacity review, and on-time delivery performance. A target of at least 95% on-time delivery is a practical benchmark for stable supply. | Capacity plan, production schedule, historical delivery records, and escalation procedure for delays. | Reliable delivery reduces production interruptions and emergency transportation costs. | Medium |
| Continuous Improvement | The supplier should use measurable improvement actions to reduce defect rates, process variation, waste, and customer complaints over time. | Improvement records, defect trend charts, audit findings, waste-reduction data, and completed improvement projects. | Continuous improvement indicates long-term manufacturing maturity and lower total cost of ownership. | Standard |
