Models of metals cracking in accidents provide insight

The connection between the micromechanical properties and crack growth when metals are exposed to permanent plastic deformation, associate professor Kim Lau Nielsen has dealt with for many years. Now also in a doctoral dissertation.

“Whether it’s the car you drive, the airplane you fly with, or the ship you board, you expect it to be able to withstand the loads during intended use – and often also with unintentional use. But such a promise is difficult to keep without insight into plastic deformation and fracture mechanics, as well as the possibility of virtual testing using computer models. My research tries to provide new modeling techniques and new knowledge about fractures in metals,” says Kim Lau Nielsen.

In that perspective, insight into the deformation and fracture of metals can ultimately save human lives, points out Kim Lau Nielsen, who in his research has developed new simulation techniques based on observations from experiments on metals, writes the Technical University of Denmark in a press release.

Aiming for use in industry

“It requires fairly efficient computer models and demonstration of their use before they find their way to industrial use, and it is my goal to create that connection,” says Kim Lau Nielsen.

Kim Lau Nielsen’s research focuses partly on bringing new plasticity theories with an underdeveloped modeling basis for practical use, and partly on utilizing the new computer models for better understanding o crack propagation in ductile metals.

“Together with national and international collaborators, we have created novel simulation techniques and procedures that acts as a bridge between the different scales in fracture mechanics. We have shown how one can convey the micro-mechanics of ductile plate tearing to large-scale practical applications and, in the process, cemented a special crack propagation mode observed when tearing thin ductile metal plates.”

Defends his doctoral dissertation

When Kim Lau Nielsen defends his doctoral dissertation, it is DTU’s vice-rector Rasmus Larsen who is the chairman.

“The technical doctorate is DTU’s highest academic distinction and is given in recognition that the candidate with the underlying research has taken the research one step further. With his studies of computer models for modeling and analysis of deformation and fractures in metals, Kim Lau Nielsen has created research that, in addition to having left its mark on the international research world, is also of great benefit to Danish production companies. I look forward to the dissertation defense,” says Rasmus Larsen.

Kim Lau Nielsen’s defense of the doctoral dissertation “Fracture and Plasticity Across Scales: Methods and Mechanisms” will take place on 11 January 2022 at 2 pm in Glassalen building 101.

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