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Abstract Coke drums are critical units in the delayed coking process to produce lightweight oil products from heavy residual oil. The fulfillment of the designed coke drum lifetime is often obstructed by low-cycle fatigue damage over cyclic thermal and mechanical loading. Considering the tremendous cost of drum replacement and production loss due to shutdown, the coke drum lifetime extension is of great economic significance in the oil and gas industry. A research project regarding coke drum fabrication and repair was initiated in the Manufacturing & Materials Joining Innovation Center (MA2JIC) at the Ohio State University in 2016. The project includes two phases of work. The first phase of the study (2016∼2019) focused on the external weld repair of coke drum materials, while the ongoing second phase of the study (2019∼2023) addressed coke drum fabrication and repair. A novel low-cycle fatigue testing approach was developed using Gleeble thermo-mechanical simulator and was applied to evaluating the performance of coke drum base materials and welded joints under cyclic deformation. The project goal is to improve the fundamental understanding of materials and joint performance that allows the optimization of coke drum design, fabrication, and repair. In this technical paper, the key methodologies and achievements of the project will be introduced, and some future work will be proposed for the next step. 

Austenitic and ferritic stainless-steel interlayers for resistance spot welding of an AlSi-coated 2000MPa UTS press-hardened boron steel and a 6022-T4 aluminum alloy were investigated to improve joint performance. CALPHAD and kinetic-based simulations were explored to determine the effects of Cr on the formation of Fe–Al intermetallic compounds. Selected area diffraction reveals the formation of FeCrAl9 along the interlayer-Al interface and suppresses the formation of FeAl3. The implementation of stainless-steel interlayers significantly improved the mechanical performance of the joint, with the 430 foil condition experiencing a substantial decrease in the Fe–Al intermetallic.