Related Experiment Video
Updated: Jun 3, 2025

07:36
Experimental Procedure for Warm Spinning of Cast Aluminum Components
Published on: February 1, 2017
9.4K
Interface Microstructure and Properties of 42CrMo/Cr5 Vacuum Billet Forged Composite Roll
Ming Li1, Zongan Luo1, Hongyu Zhou1
1State Key Laboratory of Rolling and Automation, Northeastern University, No. 3 Wenhua Road, Shenyang 110819, China.
Materials (Basel, Switzerland)
|January 11, 2025
Summary
A novel vacuum forging process creates strong 42CrMo/Cr5 composite rolls by achieving complete metallurgical bonding at the interface. This method enhances mechanical properties and overcomes limitations of traditional casting methods for industrial applications.
Area of Science:
- Materials Science
- Metallurgical Engineering
- Manufacturing Processes
Background:
- Composite rolls produced by casting often suffer from microstructural coarsening, limiting their mechanical performance.
- High-temperature exposure during preparation degrades the interface and surface layers of cast composite rolls.
Purpose of the Study:
- To develop a novel vacuum billet forging process for fabricating high-performance composite rolls.
- To investigate the interfacial microstructure and mechanical properties of 42CrMo/Cr5 composite rolls produced via vacuum forging.
Main Methods:
- Integration of numerical simulations with experimental validation for process optimization.
- Comprehensive interfacial characterization using optical microscopy (OM), scanning electron microscopy (SEM), electron probe microanalysis (EPMA), and electron backscatter diffraction (EBSD).
- Mechanical testing including Vickers hardness and tensile tests using a universal testing machine.
Main Results:
- Complete metallurgical bonding achieved with specific upsetting (40%) and elongation (<10%) reduction ratios.
- Interfacial microstructure analysis revealed four distinct zones with varying pearlite, ferrite, and chromium carbide content.
- Significant diffusion of Cr and Ni elements across the interface (Cr diffusion up to 70-90 μm) and enhanced bonding due to grain deformation and recrystallization.
- Tensile tests showed fracture on the 42CrMo side with yield strength of 371 MPa and tensile strength of 729 MPa.
- Microhardness increased smoothly across the interface from 190 HV to 305 HV, indicating good bonding.
Conclusions:
- The vacuum billet forging process effectively overcomes the limitations of traditional casting for composite roll fabrication.
- The optimized process ensures complete metallurgical bonding and desirable interfacial microstructure, leading to enhanced mechanical properties.
- The developed 42CrMo/Cr5 composite rolls exhibit excellent bonding performance and mechanical strength suitable for demanding applications.

