Latest Preprint – Enhancing the Hardness–Corrosion Balance in Lean Mg–Ca Alloys
📄 New Preprint Published
Thrilled to share our latest preprint titled “Enhancing the Hardness–Corrosion Balance in Lean Mg–Ca Alloys via Post-Extrusion Thermomechanical Processing,” led by Andrew Kim, with Sreenivas Raguraman, Adam J. Griebel, and Prof. Timothy P. Weihs (Johns Hopkins University and Fort Wayne Metals):contentReference[oaicite:0]{index=0}.
Study Overview
Lean magnesium–calcium (Mg–Ca) alloys are highly promising for biodegradable orthopedic implants due to their excellent biocompatibility and low alloying content, which minimize cytotoxicity while maintaining corrosion resistance.
However, achieving sufficient mechanical strength without compromising degradation behavior remains challenging.
To address this, the study systematically investigates post-extrusion thermomechanical routes—including equal channel angular pressing (ECAP), rolling, and annealing—to optimize the balance between hardness and corrosion performance:contentReference[oaicite:1]{index=1}.
Key Findings
- Extrusion + ECAP + Rolling + Annealing (EXT+ECAP+R+A) provided the best balance between strength and corrosion resistance.
- Hardness exceeded 70 HV, a ~50% increase compared to the extruded baseline, without elevating corrosion rates (~3.0–3.5 mm/yr).
- The strengthening arises from grain refinement and defect-assisted Mg₂Ca precipitation, achieved through combined deformation and controlled annealing:contentReference[oaicite:2]{index=2}.
- These results show that process design can overcome the limited precipitation hardening capacity of lean Mg–Ca alloys, enabling mechanical performance closer to clinical requirements.
Why It Matters
This work highlights how intelligent thermomechanical design can extend the applicability of ultra-lean biodegradable alloys.
By demonstrating that strengthening can be achieved without compromising corrosion behavior, it establishes a path forward for biocompatible, high-performance magnesium implants.
“Processing, not composition alone, dictates performance—carefully tuned deformation and heat treatments can unlock the full potential of lean alloys.”
🔗 Read the full preprint here → DOI: 10.21203/rs.3.rs-7594666/v1
Acknowledgments
Andrew Kim acknowledges support from the Johns Hopkins Provost’s Undergraduate Research Award.
This work was supported in part by the National Science Foundation (DMR-2320355) and conducted in collaboration with Fort Wayne Metals and the Hopkins Extreme Materials Institute:contentReference[oaicite:3]{index=3}.
#Magnesium #Biomaterials #BiodegradableImplants #MaterialsScience #AlloyDesign #Corrosion #Metallurgy #ThermomechanicalProcessing #MgCa