The aim of this master thesis work is to compare the different methods for quenching small plate samples both with the results from production quenched plates from different quenchers and standard laboratory methods like Jominy testing and dilatometer testing for evaluating CCT diagrams.
Quenching of Plate Samples
Quenching of same plate samples will be tested in 2 different equipments:
Lab quencher in SSAB EMEA Oxelösund
Lab quencher at the new R&D Center at Montpellier, SSAB Americas.
The chosen steel grades and quenching parameters have to be agreed upon and the testing may need to be started some time before the master thesis work begins. Cooling rates will be recorded for comparison with other test methods.
The possibilities to study quenching of thick plates will be investigated and maybe some adjustment of the equipment has to be considered.
Evaluation will be performed by hardness testing over the thickness and metallographical investigations.
Standard jominy testing will be performed and evaluated. Thin plates may need to be welded together before machining the specimen.
CCT diagram will be determined for some of the studied steel grades. The results will be compared with computer calculated CCT diagrams.
This part may be deleted since Swerea-Kimab will have to move their equipment early 2012.
Quenching in Brine
Small samples of the steel grades will be quenched in brine for comparison.
Test coupons from some steel grades quenched in at least one production quencher will be studied for comparison with the lab experiments. Process parameters may be varied when possible but at least recorded deliberately. Mechanical properties and microstructure will be evaluated.
Evaluation and Reporting
All experiments will be documented in a report.
The efficiency of the different methods will be evaluated and recommendations for how to receive relevant results by lab quenching. Recommendation for a span of quenching parameters in the lab quencher experiments will be proposed.
The master thesis will be performed mainly at the lab in Oxelösund.
The student will need support from a project group with at least one member from R&D Center in Montpelier and one from the product development group in Oxelösund.
Bertil Ahlblom, 0155-254324,
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