Bibliographic record
Abstract
Where light-weight components are desired, e.g. in automotive and aerospace applications, magnesium can provide an important advantage over other structural materials such as aluminum and steel. The density of magnesium is two thirds that of aluminum and a quarter that of galvanized steel. The combination of low density and reasonable strength of magnesium leads to a specific strength, which is much higher than that of steel or aluminum. Stiffness is often as important as strength and, with respect to bending stiffness, magnesium offers major advantages over both steel and aluminum. Using more magnesium would significantly decrease the weight of automobiles, which is one of the important goals in automobile design. However, usage of magnesium lags far behind that of aluminum. To date, most magnesium applications in the automobile industry are in the form of die cast parts. Wrought magnesium, particularly in the form of sheet, represents a tremendous growth opportunity in the application of magnesium, e.g. inner door panel, engine bonnet, seat components, roof, and fenders. The use of magnesium sheet is, however, severely limited because of: (a) the high cost of magnesium sheet, (b) the poor room temperature ductility of magnesium, and (c) the relatively high propensity to corrosion. Sheet materials are required to display sufficient formability when subjected to bending stresses during fabrication into parts. The poor plastic flow characteristics of magnesium at room temperature have considerably hampered its sheet applications. Essentially, because magnesium has a hexagonal close packed (hcp) structure, active slip systems at low temperatures are mainly limited to those involving basal planes. This is because the critical resolved shear stress (CRSS) for basal plane slip in magnesium single crystal is 100 times lower than that for non-basal plane slip (prismatic or pyramidal planes) near room temperature. Thus, the distribution of basal planes (0001) in magnesium plays an important role in determining formability at low temperatures. As the temperature increases, the CRSS of the non-basal slip systems decreases and, therefore, there is a significant increase in formability. Consequently, sheet forming at elevated temperatures is one possibility that is being contemplated, and there is considerable ongoing research in this general area, including those concerned with the viability of superplastic forming. In this chapter, the challenges to the production of magnesium sheet and the route toward overcoming them are explained. Then, deformation characteristics of magnesium and associated mechanisms are discussed.
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 | 0.002 | 0.002 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.003 | 0.005 |
| Open science | 0.002 | 0.002 |
| Research integrity | 0.004 | 0.003 |
| Insufficient payload (model declined to judge) | 0.020 | 0.009 |
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".