| Quality management system | Supplier operates a documented quality management system aligned with ISO 9001:2015. | Current certification Certificate scope should cover the relevant manufacturing or processing activities. | Valid certificate, certification scope, certificate number, issuing certification body, and expiry date. | Improves process control, corrective action management, document control, and audit readiness. |
| Batch traceability | Each shipment can be traced from raw-material lot to production batch and final inspection records. | Full lot traceability Unique batch or lot identification is shown on packaging and quality documents. | Batch number, production date, raw-material lot, furnace or sintering record, inspection report, and shipment record. | Supports root-cause analysis, controlled recalls, repeat purchasing, and consistent quality across international shipments. |
| Certificate of analysis | Every commercial batch is supplied with objective test data rather than only a general product datasheet. | Report includes grade, dimensions, density, hardness, transverse rupture strength where applicable, and inspection results. | Signed or digitally controlled certificate of analysis linked to the shipped batch number. | Allows incoming inspection results to be compared with the agreed technical specification. |
| Tungsten carbide grade selection | Grade is selected according to wear, impact, corrosion, and machining requirements. | WC-6Co: higher hardness and wear resistance. WC-10Co to WC-12Co: higher toughness and impact resistance. | Material specification, nominal cobalt content, grain-size range, and application recommendation. | Cobalt content and carbide grain size directly influence the balance between hardness, toughness, and wear performance. |
| Carbide grain size | Specify the nominal WC grain-size category instead of using only a generic “carbide” description. | Submicron: approximately 0.2–0.8 μm. Fine: approximately 0.8–1.3 μm. Medium: approximately 1.3–2.5 μm. | Metallographic report, grain-size method, and agreed tolerance or classification. | Smaller grains generally support higher hardness; larger grains can provide improved toughness for demanding impact conditions. |
| Dimensional capability | Dimensions, tolerances, surface finish, chamfers, holes, and edge conditions are defined on the drawing or purchase specification. | Supplier confirms achievable tolerances before quotation and identifies whether dimensions are supplied as-sintered, ground, or polished. | Inspection report, calibrated measurement records, capability study, and approved drawing revision. | Reduces rework, assembly problems, and disputes caused by different interpretations of finished dimensions. |
| Porosity and structural integrity | Material is free from unacceptable pores, cracks, deleterious phases, and abnormal binder segregation. | Acceptance limits are defined in the purchase specification and verified by metallographic or non-destructive inspection where required. | Microstructure images, metallographic evaluation, ultrasonic or visual inspection records, and nonconformance reports. | Internal defects can reduce strength, fatigue life, sealing performance, and resistance to chipping. |
| Coating or surface treatment | Any coating, polishing, brazing preparation, or surface treatment is specified separately from the carbide substrate. | Coating chemistry, thickness range, adhesion requirement, surface roughness, and inspection method are documented. | Coating certificate, thickness measurement, adhesion test where applicable, and surface-finish report. | Prevents confusion between the performance of the substrate and the performance of the applied surface treatment. |
| Minimum order quantity (MOQ) | MOQ is stated separately for standard grades, custom dimensions, tooling, and special coatings. | Standard items: often negotiable by piece or small production lot. Custom items: commonly require a tooling charge and a larger repeat-order commitment. | Quotation showing MOQ, tooling cost, sample quantity, price breaks, and validity period. | Clarifies inventory exposure and prevents a low unit price from hiding an unsuitable minimum commitment. |
| Sample and first-article policy | Supplier provides representative samples before mass production and confirms how sample approval affects production release. | Sample dimensions, grade, inspection criteria, approval status, and permitted deviations are recorded. | Sample inspection report, first-article approval, retained sample identification, and signed technical agreement. | Enables design validation without committing immediately to the full production quantity. |
| Production lead time | Lead time is divided into tooling, raw-material preparation, sintering, grinding, inspection, and export packing. | Quoted lead time includes a defined start point and excludes or identifies approval delays and force-majeure events. | Production schedule, order acknowledgment, capacity confirmation, and shipment milestone updates. | Supports realistic inventory planning and comparison of suppliers in different regions. |
| Packaging and corrosion protection | Parts are individually or compartmentally protected against impact, contamination, and moisture during international transport. | Packaging prevents edge chipping and mix-up of batches; outer cartons carry part number, quantity, and lot number. | Packaging specification, photographs before dispatch, packing list, and batch labels. | Proper packaging reduces transit damage and preserves traceability after customs clearance and warehouse receipt. |
| Trade and payment terms | Quotation clearly states currency, Incoterms® rule and named place, payment schedule, taxes, freight responsibility, and validity. | Commercial terms are comparable across all shortlisted suppliers and do not rely on ambiguous delivery wording. | Formal quotation, pro forma invoice, purchase contract, and agreed Incoterms® 2020 term. | Creates a comparable landed-cost calculation and reduces disputes over freight, insurance, customs, and delivery responsibility. |
| Change-control process | Supplier must notify the buyer before changing grade, powder source, tooling, process route, inspection method, or subcontractor. | Prior written approval Changes are linked to a new revision or formal deviation approval. | Change-notification procedure, revised specification, deviation request, and requalification record where necessary. | Protects consistency during repeat orders and prevents unapproved process substitutions. |