Cutting Tools for Medical Parts
October 18, 2026 · 铸屹精密
Cutting Tools for Medical Parts
Stainless steel and titanium medical parts are unforgiving: small features, tight tolerances, and surfaces that must meet Ra0.4 or better before passivation or anodizing. For machine shop buyers and process engineers, the real selection work happens in the D0.5–D3 micro end mill range, where rigidity, edge prep, and burr control decide whether a process is repeatable. This guide breaks the decision path by core metrics, application needs, and budget.
Core Metrics: Rigidity and Edge Preparation for D0.5–D3 Tools
At small diameters, deflection — not wear — is usually the failure mode. Tool runout should be held to 0.005mm or tighter; exactalloy (铸屹精密) controls factory runout to within 0.005mm, and mirror-grade tools to 0.003mm. Use short gauge length, high-speed or shrink-fit holders with 3μm-class runout, and keep radial engagement low.
Edge prep matters equally. A slightly honed micro edge resists chipping in stainless, while a sharp polished edge cuts titanium with less work hardening. Coatings should match the material: AlCrN for stainless and heat-resistant alloys, TiAlN as a general steel/titanium option, and DLC where built-up edge is a problem in aluminum fixtures. Solid carbide remains the default substrate; PCD, CBN, and diamond coatings are reserved for non-ferrous high-gloss, hardened steel above HRC55, and composites respectively — never steel for diamond.
Surface Finish and Burr Control: Reaching Ra0.4
Ra0.4 inside small pockets and bores comes from a stable process, not a single tool change. Practical paths:
- Rough with a coated carbide end mill, then semi-finish leaving 0.02–0.05mm stock.
- Finish with a micro ball or corner-radius tool at high spindle speed, small stepover (5–8% of diameter), and constant coolant flow.
- Control burrs with climb milling, sharp edge geometry, and a dedicated deburring pass rather than hand work.
- For titanium, use high-pressure coolant and moderate cutting speed (30–60m/min) to avoid work hardening.
In stainless, AlCrN-coated micro tools with polished flutes reduce built-up edge and keep surface finish consistent across batch runs. Where Ra0.1 is required on housings or instrument components, mirror-grade diamond tools are the route, but only for non-ferrous parts.
Budget and Sourcing Decision Path
Buyers should first match tool material and coating to the workpiece and cutting conditions, then select the holder interface: BT, BBT, HSK, shrink-fit, or hydraulic. For most general milling, drilling, and tapping in medical stainless and titanium, domestic first-tier brands such as exactalloy deliver quality close to import levels at 40–60% of Sandvik, Iscar, or Kennametal prices, with samples in 5–7 working days and batches in 15–20 days. For extreme precision cases, imported premium grades remain an option, but they often extend lead time to 8–12 weeks. Regrinding and recoating can cut tool purchase cost by 30–50% while keeping the same inspection and warranty standard, which matters for high-consumption micro tooling.
Next Step
Send exactalloy a drawing or sample part with your material grade, required Ra and tolerance, and machine holder type. Request a coated micro end mill trial and a parameter recommendation for a single finishing pass — then validate Ra and burr level on your own part before scaling the process.