Prof. Hugo Lopez's Research

Materials Research

Fig. 1. Fracture surface in Inconel 690 after exposure to simulated hydrogen containing PWR environments at 360oC.

Prof. Lopez’s research has been focused on (a) the environmental degradation of advanced engineering alloys such as HSLA steels and Inconel alloys exposed to hydrogen containing environments, (b) Cobalt and Ni-based alloys for implant applications and materials biocompatibility, (c) Kinetics of solidification and phase transformations in cast and wrought alloys and (e) nanostructural materials processing and performance.

 

Current Research is aimed at unfolding the active mechanisms involved in the athermal and isothermal martensitic phase transformation exhibited by Co-Cr-Mo-C alloys used in the manufacture of HIP implants.   In addition, work on high temperature alloys has been focused on the thermodynamic and kinetic evaluations of stress corrosion cracking and hydrogen permeability in Inconel alloys 600 and 690.  Other work considers the effect of surface coatings with ceramic nanoparticles on the high temperature stability of FCC alloys, including computer simulation and molecular dynamics.

Materials Research

Fig. 2. Isothermal (right side) and athermal e-martensite during isothermal ageing.

In the field of solidification kinetics, active collaboration with Prof. E. Fras of the University of Mining and Metallurgy has lead to numerous publications on analytical modeling of cast iron solidification.  Current work is aimed at processing ultra-thin wall ductile iron with wall thicknesses of less than 3 mm.

Materials Research

Fig. 3. Thin wall casting of a blade rotor made of nodular cast iron. The micrograph covers the full blade cross section which measures 1 mm in length.