Engineering boundary
Supports engineering review and feasibility assessment. Not a substitute for qualified engineering judgment, testing, certification, or regulatory approval.
Public example
Industrial NiTi wire Screening Record
A realistic industrial actuator concept you can inspect without creating an account. This record separates typed demand from demonstrated capability.
Curated public example. Not a live Screening Record for your program. Not certification or regulatory approval.
Concept inputs
- Geometry: one straight NiTi wire, 0.5 mm diameter, 100 mm active length
- Requirements: 80 N force, 3 mm stroke, 20–70 °C window
- Timing and life: 1 s response target, 200,000-cycle life requirement
- Path: Joule heating, natural convection, bias-spring reset
- Evidence: no lot-specific test evidence attached
Engineering disposition
Engineering review required
Next action: establish lot-specific stress and strain limits, transformation temperatures, and the loaded path before defining a controlled-test envelope.
Reported blockers
- Axial stress demand is calculated, but capability remains unassessed until a cited allowable is on the record.
- Required strain is calculated, but stroke capability remains unassessed until documented strain capacity is on the record.
An adverse overload case on the same wire (350 N, 12 mm stroke) revises the concept instead of sharing this disposition. Candidate for controlled testing is reserved for cited stress and stroke that both meet.
Requirement checks
| Check | State | Record |
|---|---|---|
| Nominal axial stress | Unassessed | Demand 407.44 MPa from 80 N and 0.5 mm diameter. No cited allowable on the record. |
| Required stroke | Unassessed | Required strain 3% from 3 mm over 100 mm. Strain capacity not documented. |
| Heating and cooling path | Stated, not calculated | Joule heating and natural convection recorded. No measured time constant. |
| Reset architecture | Recorded, not proven | Bias spring named. Reset under load is not demonstrated. |
| Loaded actuation shift | Open | No lot-specific loaded actuation evidence attached. |
| Durability | Open | 200,000-cycle life is a requirement, not a predicted life. |
Recommended validation
- Lot-specific DSC transformation temperatures (ASTM F2004)
- Tensile stress-strain with a cited allowable for this diameter and condition
- Loaded force-displacement under the bias-spring path
- Measured heating and cooling time on the stated thermal path
- Staged functional fatigue plan before any 200,000-cycle campaign
Assumptions
- One uniform circular straight wire carries the full axial load.
- No lot certificate, supplier allowable, or lab report is attached.
- Attachment and grip stress concentrations are out of scope for this screening.
Limitations
- Outputs are mechanism-level screening, not certification, qualification, or regulatory approval.
- Physical validation is required before design commitment.
- Structural fatigue statements stay open until a validated fatigue-life model is attached.