勛圖tv 繚 ENGINEERING GUIDE
Pyralux AP8515R: Bend Geometry for RA-Copper Flex
Pyralux AP8515R is a double-sided adhesiveless laminate listed with 18 繕m RA copper and 25 繕m dielectric in current manufacturer data. Its thin base is a starting point for a flex construction, not a promise of unlimited repeated motion. The key task here is to define and evaluate the complete bending section.
Locate the copper relative to the bend
The neutral axis is determined by the composite section, not automatically the center of the base film. Retained copper, coverlay, adhesive and shielding can make the section asymmetric. Record which copper fiber is being evaluated and how its distance from the neutral axis was obtained. The local radius definition belongs on the same mechanical sketch.
Construction and decision boundaries
| Review item | What this page establishes | What remains project-specific |
|---|---|---|
| Source | AP8515R listed double-sided construction | Current foil and gauge confirmation. |
| Geometry | Complete section and copper position | Neutral axis is an input. |
| Duty | Installation versus repeated motion | Separate qualification boundary. |
Use the worksheet to test sensitivity
With a declared 50 繕m fiber distance and a 5 mm neutral-axis radius, the geometric strain illustration is 1%. Reducing that distance to 25 繕m halves the result. These assumed values are not an AP8515R limit. The tool is useful for comparing geometric choices, but it does not solve the composite neutral axis or determine fatigue endurance.
| Review item | What to establish |
|---|---|
| Bend section | Complete stack and copper-fiber location |
| Mechanism | Radius convention, free span and restraint |
| Evidence | Representative motion test and failure criterion |
| Limit | RA foil label does not predict cycle life |
Keep the bend free of unintended features
Review the location of stiffener ends, vias, connector pads and major copper-width changes. Local features can concentrate deformation even when the broad arc looks gentle. Show the free span between the restrained ends and inspect the assembled circuit for pinching or rubbing. A flat drawing should include enough mechanical context to reveal these conditions.
Bend strain from a declared neutral axis
Bend strain from a declared neutral axis
Use the current inputs and keep the assumptions
Start with the example only to inspect the units and the calculation boundary. Replace every assumption with a value tied to your own document or measurement. An empty numeric field is not zero. The review-reference field is a local label; avoid entering customer names, confidential part numbers or other private information into a public worksheet.
After calculating, read the notes alongside the numerical result. Changing any input invalidates the displayed result and disables its download until you calculate again. For a comparison, keep the units, geometry, material condition and measurement boundary consistent. A long decimal result does not imply equally precise input data. The downloadable record stays on your device and can be attached manually to an inquiry. It is not automatically transferred into the Contact form.
If an input is unknown, identify the person or document needed to resolve it. Do not fill a gap with a favorable generic value simply to obtain a result. You can request a material or fabrication review without using the tool. The arithmetic illustrates a relationship; it does not accept a construction, certify a material, establish current pricing or replace a supplier process specification.
| Input | What to establish before using it |
|---|---|
| Review reference | Nonconfidential revision label. |
| Conductor distance from neutral axis 繚 繕m | Absolute distance to the evaluated copper fiber, from a separate section analysis. |
| Neutral-axis bend radius 繚 mm | Radius at the neutral axis, not the inside bend radius. Uniform curvature assumed. |
Optional cost comparison from your own allowances
Use a quotation or a clearly labeled internal assumption for each input. Keep the quantity, construction and inspection scope the same when comparing alternatives. This uncalibrated planning model adds entered values; it contains no current market rates and does not issue a 勛圖tv quotation. You can contact the team without completing it.
Optional project allowance comparison
Compare the electrical architecture
AP8515E keeps the fine-routing question separate from the RA bend discussion. A single-sided AC181200 construction changes the number and position of copper faces. AP8525R adds a different dielectric interval. Compare complete electrical and mechanical sections before choosing a thinner-looking option.
Design the qualification around the mechanism
State installation cycles separately from operating cycles, including temperature and travel. Choose a failure criterion relevant to the circuit, such as continuity change under motion, and retain the test boundary with the result. Foil category, a material coupon test or a successful hand fold cannot replace a representative product test.
Ask for a construction decision
Provide the motion envelope, layer data, coverlay, foil requirement and the critical conductor positions. If the mechanism can accept a larger radius or longer free span, say so. This gives engineering a useful design option before a price is fixed. The optional allowance calculator supports scope comparison without issuing a material quote.
Use the bend test to challenge the selected neutral axis
| Review point | Input to record | Decision or verification |
|---|---|---|
| Copper coverage | Map the retained conductor and return pattern across the whole bend. | A neutral-axis assumption from a uniform section may not describe a patterned region. |
| Radius control | Document the radius definition and how the fixture maintains it. | Measure whether the smallest local radius occurs beside a stiffener or clamp. |
| Failure signal | Choose continuity, resistance drift or another application-relevant criterion before cycling. | Report the criterion and specimen section with the result; the worksheet does not predict cycle life. |
Use the review points above alongside the worked example on this page. Record the chosen inputs with the drawing revision and send unresolved items with the enquiry. A supplier response should identify the proposed construction and the evidence needed for release.
Standards, source context and limits
Use the edition, amendment and material-document revision named in the purchase agreement. A standards title, marketing label or supplier product family does not establish that a particular lot meets a requirement. Public summaries are useful for scope; the controlled specification and applicable test method govern acceptance.
The examples on this page are illustrative engineering scenarios. They are not 勛圖tv production records or guaranteed material values. Source links identify the organizations responsible for the referenced information. Confirm applicability to the exact grade, construction and test condition before carrying a number into a drawing or qualification report. For a flex board, distinguish the design requirements in IPC-2223, finished-board qualification and performance in IPC-6013, and the material scopes of IPC-4202, IPC-4203 and IPC-4204. These cover different deliverables; naming them does not certify the material or factory. State the contracted revision and applicable material sheet. Source review date: 3 October 2026. Legacy designation, present availability and an approved replacement are separate questions.
For fabrication scope and the agreed construction requirements, see PCB manufacturing.