Effect of temperature and strain rate on the constitutive behaviour of oriented polypropylene tubes
Bibliographic record
Abstract
The lighter weight of thermoplastics compared with metals make these materials an attractive alternative for automotive structural components. In particular, oriented thermoplastic tubes, typically uniaxially or biaxially oriented by an extrusion process, possess increased strength along the orientation directions. In addition to their good strength, the ductility of these materials, when formed at elevated temperatures, is also improved. For development of analytical and/or finite element models of the elevated-temperature forming of uniaxially oriented thermoplastic tubes, suitable constitutive models describing the temperature- and strain-rate-dependent stress—strain behaviour of the material along the axial (or orientation) and hoop (perpendicular to orientation) direction are required. The behaviours along both directions of the tube are required since its properties are anisotropic as a result of the extrusion process. The G'Sell et al. constitutive model, modified in this study to account for the effect of temperature, was shown to capture the uniaxial behaviour of oriented polypropylene tubes accurately along the axial and hoop direction at a range of elevated temperatures and strain rates.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".