Projects / Programmes
Evolution of microstructure and properties of welding joints in thermal pover works operating at high temperature
| Code |
Science |
Field |
Subfield |
| 2.04.00 |
Engineering sciences and technologies |
Materials science and technology |
|
| Code |
Science |
Field |
| T150 |
Technological sciences |
Material technology |
| T450 |
Technological sciences |
Metal technology, metallurgy, metal products |
alloyed steels, welding joints, microstructure, creep resistance, komponents for thermal power work
Researchers (12)
| no. |
Code |
Name and surname |
Research area |
Role |
Period |
No. of publicationsNo. of publications |
| 1. |
08236 |
Boris Arzenšek |
Materials science and technology |
Researcher |
2004 - 2007 |
225 |
| 2. |
00741 |
Bojan Breskvar |
Materials science and technology |
Researcher |
2004 |
160 |
| 3. |
17161 |
Roman Celin |
Materials science and technology |
Researcher |
2004 - 2007 |
285 |
| 4. |
08797 |
MSc Tatjana Drglin |
Cardiovascular system |
Researcher |
2004 - 2005 |
33 |
| 5. |
04982 |
Dimitrij Kmetič |
Materials science and technology |
Researcher |
2004 - 2007 |
421 |
| 6. |
23593 |
PhD Gorazd Kosec |
Materials science and technology |
Junior researcher |
2004 - 2007 |
229 |
| 7. |
04254 |
PhD Janez Šetina |
Electronic components and technologies |
Researcher |
2004 - 2007 |
251 |
| 8. |
13026 |
PhD Roman Šturm |
Manufacturing technologies and systems |
Researcher |
2004 - 2005 |
329 |
| 9. |
08195 |
PhD Borivoj Šuštaršič |
Materials science and technology |
Researcher |
2004 - 2007 |
412 |
| 10. |
05438 |
PhD Matjaž Torkar |
Materials science and technology |
Researcher |
2004 - 2007 |
469 |
| 11. |
17185 |
Gvido Velikajne |
|
Technical associate |
2004 - 2007 |
192 |
| 12. |
09788 |
PhD Jelena Vojvodič Tuma |
Civil engineering |
Head |
2004 - 2007 |
629 |
Organisations (1)
Abstract
The most important part of termal power works, where steam is overheated are connected in a closed system with welding joints. The temperature in these parts is sufficient to induce changes of microstructure and a gradual decrease of steel creep resistance. Due to the difference in local heating temperature and cooling rate after welding, joints have a very heterogeneus microstructure. During the operation also in these joints changes occur, which affect the microstructure and the creep resistance. Earlier investigations have shown f.i. that the creep resistance of a steel was decreased by appr. 4 times, when the internal recrystallisation changed the microstructure from tempered martensite to an homogeneus distribution of carbide particles in ferrite grains, although no significant change in the size of carbide particles was established. It is clear, thus, that the creep resistance depends strongly also on the morphology of the microstructure rsp. of the carbide particles distribution.
In welded joints part of the microstructure is produced at solidification and part with transformation of austenite heated at different local temperature and cooled at different rate. F.i. the austenite grain size is by appr. one order of magnitude greater in the contact layer solid-liquid steel than in the area, where the temperature was of 1000 oC or lower. The difference in grain size induces a difference in hardenability, which is reflected in a variety of microstructures, carbide particles distribution and hardness significantly different than those in the welded steel. For this reason, it is assumed that the morphology and kinetics of microstructure changes in welding joints differ of those in the welded steel. These changes and their effect on creep resistance will be investigated in this project.
