For automotive MIM programs (IATF 16949), three core documents form the backbone of the quality planning system. Understanding what each contains — and how they relate — is essential for anyone managing MIM supplier quality.
The three documents:| Document | What It Describes | When Created | Key Contents |
|---|---|---|---|
| Process Flow Diagram (PFD) | The sequence of all manufacturing steps from incoming material to shipment | First — before PFMEA and control plan | Step numbers, operation descriptions, inspection points, material flow |
| PFMEA (Process Failure Mode Effects Analysis) | For each process step: what could go wrong, how severe it would be, and what controls prevent it | Second — uses the PFD as input | Failure modes, effects, causes, current controls, RPN, recommended actions |
| Control Plan | For each process step: what will be checked, how often, by whom, and what to do if it goes wrong | Third — uses PFMEA outputs | Control methods, sample size, frequency, reaction plans |
| Document | Entry for Sintering |
|---|---|
| PFD | Step 30: Sintering — continuous belt furnace, 1350°C, H₂ atmosphere |
| PFMEA | Failure: Temperature drift beyond ±5°C. Severity: 8 (high). Cause: Thermocouple degradation. Current control: Weekly temperature profiling with traveling thermocouple. RPN: 64 |
| Control Plan | Parameter: Soak zone temperature. Method: Furnace controller chart + weekly profile. Sample: Continuous recording. Reaction: If profile shows >±5°C deviation, quarantine last 2 batches and re-profile |
A Process Flow Diagram maps the sequence of MIM manufacturing steps. A PFMEA identifies potential failures at each step, their severity, and the controls that prevent them. A Control Plan specifies how each step will be monitored — what to check, how often, and what to do if it goes wrong. All three are required for automotive MIM under IATF 16949.