Fig xA Macroscopic appearance of the failed
Chemical composition of the Voreloxin material and weld joint of the CWP (wt%).ElementCCrNiMoNDSS of the flange0.01522.218.104.22.168DSS of the cylindrical body0.01922.525.473.020.17Weld joint0.3522.214.171.1240.11ASTM-A790/A790M-09<0.0321.0–23.04.5–6.52.5–3.50.08–0.20GB/T 21833<0.0321.0–23.04.5–6.52.5–3.50.08–0.20Full-size tableTable optionsView in workspaceDownload as CSV
3.1.2. Metallographic structure
Fig. 4. Metallographic structures of the DSS: (a) flange (b) cylindrical body and (c) butt weld.Figure optionsDownload full-size imageDownload as PowerPoint slide
Fig. 5. EBSD of the butt weld.Figure optionsDownload full-size imageDownload as PowerPoint slide
3.1.3. Mechanical test
In order to identify whether the DSS used in the water circulating pump is qualified, the impact toughness of samples from the flange and the cylindrical body were tested respectively by the method of Charpy impact test. It revealed that the Charpy impact value of the flange and the cylindrical body is both greater than 300 J, exhibiting a superior toughness quality. To further investigate into the toughness of the base material, SEM morphology analysis was applied. As seen in Fig. 6, a number of dimples were found on the Chary impact fractography under magnification of 500, confirming the excellent ductility of the DSS used in CWP.