Norwegian version
Rafael Borrajo

Rafael Borrajo

About

Rafael Borrajo is an associate professor in Mechanical Engineering. His research is focused on materials innovation and characterization, and the use of ion and nanoparticle beams to create/modify materials. Furthermore, he is responsible for the teaching of two courses: Materials Technology and Hydraulics and Machine Systems.
Dr Borrajo completed a MSc (2012) and a PhD (2014) with a focus on material science and space propulsion at the University of California in Irvine, under the supervision of Prof. Gamero-Castaño. He investigated space thrusters (electrosprays) and their interaction with solid surfaces. He studied the energetic impact of electrosprayed nanodroplets on hard crystalline materials, and characterized the resulting surface modifications, e.g. material removal (sputtering), topographic changes and nano-structural transformations (amorphization), to find out the physical mechanisms involved in these phenomena.
As a post-doctoral researcher in the Dpt. of Materials Science and Engineering at KTH in Stockholm, he investigated super-hard composite materials and steels. He participated in the development of cemented carbides and, through materials characterization, provided insight about the effect of the manufacturing process (sintering) and thermal treatment in their resulting nano-structure and properties. In addition, he studied the optimization of steel by controlling phase decomposition and particle precipitation in the nano- and micro-scale. Through his work on materials characterization, he has acquired expertise in the following techniques: scanning electron microscopy (SEM), transmission electron microscopy (TEM), TEM sample preparation with focused ion beams (FIB), electron backscatter diffraction (EBSD), x-ray diffraction (XRD), energy-dispersive x-ray spectroscopy (EDS) and atomic force microscopy (AFM).
As a propulsion engineer at OHB Sweden, Dr. Borrajo worked on systems engineering and developed propulsion systems for spacecraft. He collaborated with Luleå Technical University to find new methods for satellite propellant gauging in-orbit, and with the European Space Agency (ESA) in the design of spacecraft power and propulsion systems with a simpler, lighter and more cost-effective structure.
As a research engineer at the Norwegian company Cardiaccs, Dr Borrajo worked in the development of heart sensors for the monitoring of the cardiac function in real-time to prevent complications during open-heart cardiac surgery.
Formerly at Yale University, Dr. Borrajo conducted pre-doctoral research working with Prof. Fernandez de la Mora. He took part in the development of analytical instrumentation based on ion mobility and mass spectrometry, with the capability to separate and identify traces from gas mixtures in very low concentrations, enabling real-time chemical/medical diagnosis. As examples of his research, he studied the real-time separation of traces in room air for explosive detection, the chemical patterns in human breath and skin vapours for the detection of disease markers (cancer), and biometric identification of people.
Dr. Borrajo completed a BSc (2008) in industrial engineering at the University of Malaga, in Spain. As part of his BSc dissertation, he performed research on fluid/thermal numerical simulations of heat exchangers using computational fluid dynamics (CFD).

Fields of study

Subject areas

Semiconductors   Hydrodynamics   Nanotechnology   Mass spectrometry   Spacecraft   Materials technology   Surface Science   Process metallurgy   Material characterization

Research projects

Scientific publications

Keprate, Arvind ; Woodford, Sam ; Borrajo, Rafael (2023). From Theory to Practice Leveraging Project Based Learning to Cultivate Student Engagement in Mechanical Engineering Education. ., . (Ed.). IEEM 2023 IEEE International Conference on Industrial Engineering and Engineering Management Singapore 18 - 21 December 2023. IEEE conference proceedings.
https://doi.org/10.1109/IEEM58616.2023.10406362

Borrajo-Pelaez, Rafael ; Hedström, Peter (2018). Recent Developments of Crystallographic Analysis Methods in the Scanning Electron Microscope for Applications in Metallurgy. Critical reviews in solid state and materials sciences. Vol. 43.
https://doi.org/10.1080/10408436.2017.1370576

Nosko, Oleksii; Borrajo-Pelaez, Rafael ; Hedström, Peter; Olofsson, Ulf (2017). Porosity and shape of airborne wear microparticles generated by sliding contact between a low-metallic friction material and a cast iron. Journal of Aerosol Science. Vol. 113.
https://doi.org/10.1016/j.jaerosci.2017.07.015

Ma, Taoran; Borrajo-Pelaez, Rafael ; Hedström, Peter; Blomqvist, Andreas; Borgh, Ida; Norgren, Susanne; Odqvist, Joakim (2017). Liquid Phase Sintering of (Ti,Zr)C with WC-Co. Materials. Vol. 10.
https://doi.org/10.3390/ma10010057

Ma, Taoran; Borrajo-Pelaez, Rafael ; Hedström, Peter; Borgh, Ida; Blomqvist, Andreas; Norgren, Susanne; Odqvist, Joakim (2016). Microstructure evolution during phase separation in Ti-Zr-C. International Journal of Refractory Metals and Hard Materials. Vol. 61.
https://doi.org/10.1016/j.ijrmhm.2016.09.019

Borrajo-Pelaez, Rafael ; Gamero-Castaño, Manuel (2015). Ultrafast physical sputtering of GaN by electrosprayed nanodroplet beams. Materials Letters. Vol. 159.
https://doi.org/10.1016/j.matlet.2015.06.125

Borrajo-Pelaez, Rafael ; Saiz, Fernan; Gamero-Castaño, Manuel (2015). The Effect of the Molecular Mass on the Sputtering of Si, SiC, Ge, and GaAs by Electrosprayed Nanodroplets at Impact Velocities up to 17 km/s. Aerosol Science and Technology. Vol. 49.
https://doi.org/10.1080/02786826.2015.1023890

Borrajo-Pelaez, Rafael ; Gamero-Castaño, Manuel (2015). The effect of the molecular mass on the sputtering by electrosprayed nanodroplets. Applied Surface Science. Vol. 344.
https://doi.org/10.1016/j.apsusc.2015.03.077

Gamero-Castaño, Manuel; Torrents, Anna; Borrajo-Pelaez, Rafael ; Zheng, Jian-Guo (2014). Amorphization of hard crystalline materials by electrosprayed nanodroplet impact. Journal of Applied Physics. Vol. 116.
https://doi.org/10.1063/1.4901287

Borrajo-Pelaez, Rafael ; Grustan-Gutierrez, Enric; Gamero-Castaño, Manuel (2013). Sputtering of Si, SiC, InAs, InP, Ge, GaAs, GaSb, and GaN by electrosprayed nanodroplets. Journal of Applied Physics. Vol. 114.
https://doi.org/10.1063/1.4829925





These publications are obtained from Cristin. The list may be incomplete