InterstitialFree Steels Structure of Spot Welds Interstitialfree steel

Interstitial-Free Steels: Structure of Spot Welds

Interstitial-free steel Fe-0. 002 C wt% Interstitial-free and unalloyed

Extremely fast transformations Extremely fast cooling rates Phase diagram similar to pure iron Difficult to interpret structure

Interstitial-free steel Fe-0. 002 C wt%

Bundy (1965)

Completed in a time period much less than a second J. Khan, L. Xu and Y. J. Chao, Science and Technology of Welding and Joining 4 (1999) 201

austenite ferrite cementite

Physical metallurgy of spot welds in interstitial-free steels austenitic stainless ferritic stainless Bhadeshia, Vitek and David, Materials Science and Technology 7 (1991) 50

Bhadeshia, Vitek and David, Materials Science and Technology 7 (1991) 50

Carbon supersaturated plate Carbon diffusion into austenite and carbide precipitation in ferrite Carbon diffusion into austenite Carbide precipitation from austenite UPPER BAINITE (High Temperature) LOWER BAINITE (Low Temperature)

Ohmori and Honeycombe

Widmanstätten ferrite

Hayat, Demir, Acarer, Aslanar, Kovove Materialy 47 (2009) 11 Reproduced with permission

Bayraktar, Kaplan, Devillers and Chevalier, J. Mat. Proc. Techn. 189 (2007) 114 Reproduced with permission

Bhadeshia, Metal Science 16 (1982) 159

calculations 800 2 1 3 Temperature / C 700 4 5 6 600 500 1. Fe-0. 4 C 2. Fe-0. 4 C-2 Si 3. Fe-0. 4 C-1 Ni 4. Fe-0. 4 C-1 Mn 5. Fe-0. 4 C-1 Mn-1 Cr 6. Fe-0. 4 C-2 Mn 400 300 200 0 10 10 1 10 2 3 10 Time / s 4 10 10 5

Mukhopadhyay, Bhattacharya and Ray, J. Mat. Proc. Techn. 209 (2009) 1995 Reproduced with permission

Mukhopadhyay, Bhattacharya and Ray, J. Mat. Proc. Techn. 209 (2009) 1995 Reproduced with permission

Mukhopadhyay, Bhattacharya and Ray, J. Mat. Proc. Techn. 209 (2009) 1995 Reproduced with permission

Bhadeshia, Svensson & Gretoft, Acta Metallurgica 33 (1985) 1271