Integrated Computational Materials Engineering in the Hot Roll Bonding of Ultra-Thick 45 Steel Plates

To resolve the challenges of weak bonding interface and to avoid expensive and time-consuming trials, integrated computational materials engineering (ICME) was applied to study the hot roll bonding and forming of ultra-thick 45 steel stacked assemblies (>60 mm) and to optimize the rolling processes. Microstructure and properties of the continuous cast slabs of 45 steel subjected to heating and forming were acquired from JMatPro V13.2 calculations and essential experimental validations. Interfacial bonding criteria were established from hot compression tests and were applied to the finite element simulations of the multi-pass rolling processes of a two-slab stacked assembly and a three-slab stacked assembly to predict the bonding of interior interfaces and the deformation of the plates. Unlike previous studies, the aim of this research is to apply the concept of integrated computational materials engineering to shorten the development cycle and reduce re-search costs. The results revealed that the compressive strain of 0.05 is sufficient to form metallurgical bonding at the interface for machined 45 steel in a vacuum. Finite element simulation results indicate that complete bonding of the interfaces is established after two passes for the two-slab stacked plate and four passes for the three-slab stacked plate. Optimized rolling process parameters from analyzing the finite element simulation results are applied to design the hot rolling process of the stacked slab assemblies to produce ultra-thick plates. By applying the concept of integrated computational materials engineering, the development cycle of product processes can be significantly shortened, and financial investment can be reduced.