Precision Polishing & Tumbling for PM & MIM Components
Advanced Mass Finishing, Micro-Deburring, Radiusing, and Ultra-Low Surface Roughness (Ra < 0.1μm) for High-Integrity Powder Metallurgy and Metal Injection Molded Parts.
Engineered Post-Processing for High-Precision Geometries
Powder Metallurgy (PM) and Metal Injection Molding (MIM) parts require specialized mass finishing to eliminate micro-particulates, optimize friction coefficients, and deliver flawless visual appeal without degrading tight tolerances.
Non-Destructive Micro-Deburring
Complete removal of sintered parting-line flashes, gate vestiges, and micro-burrs from gear tooth profiles and complex MIM apertures while preserving sharp functional edges.
Optical Mirror Polishing
Multi-stage chemical-mechanical burnishing and centrifugal drag finishing achieve surface roughness down to Ra < 0.1μm, generating defect-free, ultra-reflective cosmetic finishes.
Precise Edge Radiusing (R-Angle)
Controlled edge conditioning with deterministic radius generation (0.05mm - 0.50mm) to eliminate notch stress, prevent micro-cracking, and facilitate seamless automated robotic assembly.
Topography Optimization
Smoothening of surface peaks while keeping porous lubricating reservoirs intact in self-lubricating bearings, drastically lowering operating friction, noise, and component wear rates.
Advanced Mass Finishing & Surface Treatment Technologies
At Ningbo Jiehuang Chiyang Electronic Tech Co., Ltd. (JHPIM), our finishing plant integrates high-energy automated machinery designed to process intricate internal passages, external contours, and miniature cross-holes.
High-Frequency Vibratory Tumbling
Utilizes multi-axis 3D inertial vibration with ceramic, plastic, or synthetic media alongside pH-buffered finishing compounds. Ideal for mass descaling, rounding, and uniform deburring of medium-to-large sintered gears, pump rotors, and tool components without component-on-component impingement.
Centrifugal Barrel & Disc Finishing (CBF)
Generates gravitational force up to 30G through planetary rotation. Provides rapid surface leveling and micro-finishing 10 to 30 times faster than conventional tumblers. Specifically tuned for micro-MIM brackets, medical blades, and delicate surgical components requiring tight geometrical integrity.
Dry & Wet Precision Grinding Media
Tailored processing modes: Wet tumbling utilizes eco-friendly corrosion inhibitors and specialized alumina ceramic media for heavy cut-down; Dry polishing applies treated walnut shells, hardwood granules, and diamond-impregnated pastes for ultra-high luster cosmetic metal finishes.
Fluidized Hydro-Polishing & Magnetic Abrasive Deburring
Specially engineered for CIM/MIM components with intricate undercut passages, internal lubrication holes, and tiny splines. Fine abrasive slurries flow uniformly through internal cavities, smoothing difficult surfaces that cannot be accessed by rigid tooling.
Uniform Surface Treatment for Complex 3D Freeform Geometries
Unlike manual grinding or unidirectional CNC line buffing, our automated mass finishing systems apply equalized isotropic friction across all 3D exterior planes, interior recesses, threaded segments, and intricate contours.
Applicable Powder Metallurgy & MIM Product Lines
Our comprehensive surface finishing is seamlessly coupled with JHPIM's near-net shape sintering facilities, offering an all-in-one manufacturing route from raw powder to ready-to-assemble components.
Sintered Gears & Transmissions
Spur gears, helical gears, planetary gear sets, bevel gears, and compound gear assemblies. Tumbling reduces tooth roughness to improve mesh acoustics, reduce pitting, and boost power transmission efficiency.
Self-Lubricating Bearings & Bushings
Iron-based and copper-based oil-impregnated spherical bearings, flanged bushings, and sleeve bearings. Precision burnishing cleans surface pores without smearing, enabling smooth hydrodynamic oil release.
MIM Precision Micro-Components
Ultra-dense stainless steel (316L, 17-4PH), titanium alloy, and tungsten carbide micro-parts. Eliminates sintering dust and binder residuals, generating ready-to-plate, biocompatible, mirror-smooth surfaces.
Structural & Lock Hardware
Automotive engine components, smart door lock deadbolts, lock cylinders, impact blocks, and power tool gearbox hubs. High-energy radiusing eliminates edge stress concentrations and improves corrosion resistance.
Custom Engineered Metal Parts
Tailor-made structural components manufactured from Iron-Carbon, Fe-Cu, Stainless Steels, and Nickel alloys based on client 3D drawings (STP, STEP, IGS, DWG), completely finished in-house.
Near-Net Shape Advantage
By leveraging >95% powder metallurgy material utilization combined with high-throughput bulk tumbling, clients realize 20%–50% cost reductions compared to multi-axis CNC milling.
Metallurgical & Mechanical Benefits of Mass Finishing
Polishing and tumbling do more than refine aesthetics. Our processes introduce compressive residual stresses, improve fatigue endurance, and optimize tribological performance.
Stress Relief & Fatigue Life
Sintering often leaves micro-stress raisers along corner boundaries. Tumbling peens the metal matrix, inducing compressive surface stress that retards crack initiation and extends dynamic fatigue life by over 40% under cyclic mechanical loads.
Corrosion Passivation Prep
Eliminating micro-crevices and sintering porosity skins denies corrosive electrolytes an anchoring point. When followed by passivation or plating, polished parts demonstrate superior ASTM B117 salt spray performance exceeding 500+ hours.
Dimensional Tolerance Control
Our engineered abrasive-to-part volumetric ratios and computer-monitored cycle times maintain part geometry within ±0.005mm. Critical features such as bore diameters, center distances, and tooth profiles remain strictly intact.
Mass Finishing Process Selection Guide
Selecting the optimal media and finishing mechanism depends on geometry complexity, material hardness, and target surface roughness specifications.
| Finishing Methodology | Typical Applications | Material Suitability | Initial Ra → Target Ra | Cycle Efficiency |
|---|---|---|---|---|
| Vibratory Tumbling (Wet) | PM Gears, Lock Bolts, Bushing Deburring | Iron Alloys, Copper, Carbon Steel | 3.2μm → 0.6μm - 0.8μm | High (Large Batches) |
| Centrifugal Barrel Finishing (CBF) | MIM Micro-Parts, Medical Tools, Wear Plates | Stainless 316L, 17-4PH, Tool Steels | 1.6μm → 0.05μm - 0.2μm | Ultra-Fast (30-60 min) |
| Dry Organic Buffing & Luster | Consumer Electronics, Architectural Locks | Titanium, Brass, Plated MIM | 0.4μm → Ra < 0.05μm (Mirror) | Medium (Final Stage) |
| Centrifugal Disc Finishing | Small Sintered Screws, Fasteners, Pins | Alloy Steels, Tungsten Carbide | 2.5μm → 0.3μm - 0.5μm | Very High (15-30 min) |
| Abrasive Slurry Flow Finishing | Multi-Cavity Valves, Fuel Injection MIM Parts | High-Density Superalloys, 316L | 2.0μm → 0.1μm (Internal) | High (Targeted Recesses) |
Supplying Global OEM / Tier 1 Industrial Leaders
JHPIM delivers surface-engineered components to B2B equipment manufacturers, automotive Tier 1/2 suppliers, and specialized engineering distributors across North America, Europe, and Asia.
Medical & Surgical
Micro-scissors, endoscopic jaw articulators, orthodontic brackets, and bone implant tools requiring electropolishing-ready, Ra < 0.1μm mirror hygiene finishes without burrs.
Automotive Powertrains
Variable valve timing (VVT) sprockets, oil pump gerotors, seat reclining planetary gears, transmission clutches, and sensor pole shoes requiring high fatigue strength and low NVH.
High-Security Hardware
Anti-drill lock cores, smart electronic lock latches, escutcheon plates, and high-tensile architectural mortise assemblies with flawless PVD-ready decorative luster.
Power Tools & Machinery
Impact wrench hammer blocks, planetary gear reducers, angle grinder bevel sets, hydraulic valve spools, and industrial automated mechanical couplings.
Rigorous Metrology & Inspection Standards
Our post-processing facility is integrated with full-suite metallurgical and metrological inspection systems to ensure total batch uniformity.
3D Optical Profilometry
Non-contact white-light interferometry and stylus profilometers verify surface roughness parameters (Ra, Rz, Rq, and Rsk) across planar and contoured surfaces to sub-micron accuracy.
CMM & Vision Inspection
Zeiss Coordinate Measuring Machines (CMM) and 2.5D optical projectors continuously verify that mass deburring processes maintain blueprint GD&T, R-angles, and dimensional tolerances.
Turnkey OEM/ODM Capability
From DFM analysis, mold tooling design, compacting, continuous mesh-belt sintering, to secondary CNC sizing, vacuum oil impregnation, and tumbling—all housed under ISO-compliant management.
Accelerate Your Project with Precision Finishing
Send us your 3D CAD models (STP / STEP / IGS / DWG) to receive a rapid Engineering DFM Surface Assessment, finishing protocol recommendation, and comprehensive B2B quote within 24 hours.