Gunnar Wijk was born 1944 and is retired from the Swedish Defence Research Agency (FOI) in Sweden, where he worked with assement of vulnerability, in particular projectile penetration, between 1996 and 2009. Before that he worked 24 years for Atlas Copco where he was design manager for percussive machine (rock drills and breakers) most of the time, during which he took a PhD in strength of materials at the Royal Institute of Technology in Stockholm. Gunnar Wijk’s work with Atlas Copco concerned the theory and practice of rock destruction as well as hammer performance.
At FOI Gunnar Wijk worked with assessment of vulnerability and particularly with projectile penetration. Eventually he suggested new models that describe rigid projectile penetration and perforation as well as the transition between rigid and eroding projectile penetration. The results are collected in a book Projectile Penetration Theory.