Weld metal microstructure analysis of 9–12% Cr steels

Specific welds for test blanket modules

“…In very rare cases formation of delta-ferrite could be detected (which is consistent to theory and other studies [24][25][26][27][28]) in the 5 mm weld and some inclusion have been found in the 10 mm weld. With a carbon content of 0.1% in the fusion zone of TIG welds decarbonisation of the filler material (see Table 1) was not observed.…”

Microstructural evolution of 9Cr–1Mo deposited metal subjected to weld heating

“…In Fig. 2b, the martensite, retained austenite and the residual ␦-ferrite seen is consistent with literatures (Babu et al, 2003;Onoro, 2006;Shiue et al, 2000). The retained austenite is seen as a film distributed along the martensite lath.…”

“…et al, 2006), as well as post-weld heat treatment (PWHT) conditions (Abe, 1984;Shiue et al, 2000), especially temperature and holding time, is also effective in obtaining the toughness at a good level. Microstructural investigations of the deposited metal of 9Cr-1Mo steel have revealed a sensitivity of Charpy testing to some factors, especially retention of ␦-ferrite (Haworth and Hippsley, 1985;Roger, 1991), retained austenite (Onoro, 2006), and untempered matensite (Mythili et al, 2003;Vijayalakshmi et al, 2000). In fact, the deposited metal of 9Cr-1Mo steel was inhomogeneous in microstructure owing to rapid solidification in single bead and microstructual evolution in multipass welding.…”

Effect of Vanadium on Microstructure and Mechanical Properties of TIG Weld Joint of China Low Activation Martensitic Steel

“…1b, at the same time there are a small amount of d ferrite, the size of which is 15-20 lm. d ferrite presents in martensitic stainless steels and the matrix of high-strength steel welds, severely reducing the mechanical properties of the weld [6,7]. The adding of 2 % W is the purpose of strengthening and stabilizing the martensite matrix.…”