Christian Mitterer

Bio: Christian Mitterer is an academic researcher from University of Leoben. The author has contributed to research in topics: Coating & Sputter deposition. The author has an hindex of 59, co-authored 374 publications receiving 12529 citations. Previous affiliations of Christian Mitterer include Austrian Academy of Sciences & Swiss Federal Laboratories for Materials Science and Technology.

Self-organized nanostructures in the Ti–Al–N system

Abstract: The phenomenon of age hardening could be evidenced in thin film applications. A model system, Ti1-xAlxN was chosen as such coatings are known for their excellent wear resistance enabling improved m ...

Microstructure and mechanical/thermal properties of Cr–N coatings deposited by reactive unbalanced magnetron sputtering

Abstract: Chromium nitride (CrN) is a hard material and a well-established coating for applications where severe corrosion and friction conditions are present. In this work, we report on the influence of nitrogen/argon flow rate ratio, ion energy and ion/atom flux ratio on the microstructure, hardness, residual stresses and thermal stability of magnetron sputtered chromium nitride coatings. The coatings were characterized with respect to thickness, morphology, chemical composition, microstructure and hardness. Hardness values up to 38.4 GPa could be obtained for stoichiometric CrN, which strongly depend on the grain size and residual stress. Thermal coating properties were evaluated using stress measurements during thermal cycling and XRD analyses after annealing at 500 and 700°C. Film stresses up to 700°C were measured from the bending of coated silicon specimens using the Stoney formula. Stress relaxation occurring during this temperature treatment strongly depends on the biaxial stresses in the as-deposited state. The interrelationships between growth conditions, microstructure, mechanical and thermal properties will be presented and discussed.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Fast parallel algorithms for short-range molecular dynamics

Abstract: Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

Phd by thesis

Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These