Crystalline texture in Zr-based alloys tubes
Bibliographic record
Abstract
Pressure tubes are the most important Zr-base components in the core of CANDU nuclear power reactors.The most important mechanisms defining the service life of pressure tubes are: irradiationenhanced coming with deformation, and the delayed hydride cracking.Both processes are determined by a few metallurgical parameters which must be exhaustively controlled: microstructure, dislocation density and texture [1], [2].Argentina has one CANDU power plant in operation since 1982 (CNE), which is now close to ending its service life.A refurbishment project is underway which will include the replacement of existing fuel channels, composed by Zr-2.5%Nb pressure tubes and Zircaloy2/4 calandria tubes.CNEA is developing a new manufacturing route for Zr-2.5%Nbpressure tubes, using a cold rolling pilger type machine instead of the cold drawing process currently performed in Canada.The new process will be performed at the Planta Piloto de fabricación de aleaciones especiales (PPFAE,CNEA).The extrusion stage produces a strong texture (crystalline preferential orientation) in the material.In this framework, in our laboratory (LMFAE), we calculate the texture factors [3], [4] from x-ray diffraction diagrams obtained from a Bruker D8 FOCUS diffractometer.A qualitative study of the texture was performed using the rocking curve method [5] (figure 1).The collected data was used to build a qualitative direct pole figure.The quantitative study was made through the calculation of Kearns factors (table 1), measuring in the θ/2θ standard way (Bragg-Brentano geometry).The results obtained from the rocking curves were quite satisfactory and they are compatible with the expected texture for the (0002) pole.This pole is essentially oriented in the transverse direction (90%), with small contributions in the radial (8%) and axial directions (2%).The Kearns factors are also in agreement with the these fractions, fulfilling the specified values (0.03≤f axial ≤0.09, 0.27≤f radial ≤0.39, 0.55≤f transversal ≤0.67, and 0.95≤∑f≤1.05[6]) within a dispersion of ±0.02.Table 1.Average Kearns factors of the Zr-2.5%Nbpressure tube.
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 | 0.000 |
| 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 | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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".