Sebastian Öhman Email & Phone Number

Västerås, Västmanland, Sverige

Uppsala, Sverige

Ph.D Student at the department of Chemistry - Ångström Laboratory, Uppsala University. Funded by Swedish Foundation for Strategic Research (SSF), in collaboration with Sandvik Coromant, Seco Tools, Chalmers University, and KTH (Royal Institute of Technology).• Developing novel synthesis routes for ceramic refractory materials by chemical vapour deposition (CVD). I was responsible for designing, constructing and operating a new CVD reactor capable of using tailorable metal-organic… Show more Ph.D Student at the department of Chemistry - Ångström Laboratory, Uppsala University. Funded by Swedish Foundation for Strategic Research (SSF), in collaboration with Sandvik Coromant, Seco Tools, Chalmers University, and KTH (Royal Institute of Technology).• Developing novel synthesis routes for ceramic refractory materials by chemical vapour deposition (CVD). I was responsible for designing, constructing and operating a new CVD reactor capable of using tailorable metal-organic reactants during depositions.• I Initiated, planned and managed several concurrent research projects and sought collaborations with other researchers with different competencies to improve our joint results.• I participated in several workshops and PhD courses related to Inorganic Chemistry, both domestically and abroad.• For various audiences, I presented and defended my research at several internationally acknowledged scientific conferences, including ICMCTF and EuroCVD.My Research Findings:• Provided new fundamental knowledge about the Al–Ti–O system.• Found new ways to circumvent energetic constraints and steer the reaction kinetics towards desired material phases with improved purities.• Expanded the fundamental theories about crystallization, nucleation and growth.• Enabled the synthesis of refractory ceramics at significantly reduced temperatures and timescales than comparable techniques.• Pioneered new ways to adapt the microstructure of the coatings, including single-crystalline growth. Show less

Stockholm, Sverige

I investigated the wear of cutting tools when machining different materials. Using various analytical techniques and knowledge from many different scientific areas, I deduced the detrimental influence of calcium on the wear of alumina-based coatings. As part of my master thesis at the company (see below), I developed an atomistic model explaining the wear behaviour on a fundamental scale, which contributed to improving the coatings’ wear resistance further.

Västberga

"Wear on Alumina Coated Tools and the Influence of Inclusions when Turning Low-Alloy Steel".Characterization of wear and adhered workpiece material on alumina coated cutting tools when turning low-alloy steel. Elucidating what influence the inclusions in the steel have to the wear of the alumina coating, using SEM, LOM, XRD, AES, Wyko and EPMA. Results indicated that calcium-containing inclusion are likely to play a significant role in the wear of the alumina coating… Show more "Wear on Alumina Coated Tools and the Influence of Inclusions when Turning Low-Alloy Steel".Characterization of wear and adhered workpiece material on alumina coated cutting tools when turning low-alloy steel. Elucidating what influence the inclusions in the steel have to the wear of the alumina coating, using SEM, LOM, XRD, AES, Wyko and EPMA. Results indicated that calcium-containing inclusion are likely to play a significant role in the wear of the alumina coating. AES-results demonstrated that a significant amount of calcium was present inside the worn alumina coating layer. This suggests that a reaction between the layer and the calcium-containing inclusions in the steel can occur, thus suggesting for a chemical wear mechanism. In addition, a new ground-breaking wear model has been proposed describing the wear of the alumina coating on an atomic scale. In this model, it is emphasised that the sliding of hard inclusions in the steel might trigger the activation of pyramidal slip systems in the textured alumina coating. This causes a local nano-crystallisation/amorphisation, which is believed to further facilitate the wear of the alumina coating on these tools. Show less

Gimo

Worked hands-on as a shift operator for different PVD systems (Oerlikon Balzers) used to coat cemented carbide. I was responsible for the continuous operation and upkeep of the systems. The work demanded great sense of care as the coating process was the last step before packaging and delivering to customers.

Forsbacka

Process optimization of cooling system for hardening of steel. Investigations and documentations of several different process parameters, hardness testing and metallographic investigations. Conclusions made by usng several statistical methods, including Student's T-test and analyses of variance (ANOVA).

Gimo

Summer internship as operator, preparing orders for packaging and delivery to customers

Doctor Of Philosophy - Phd, Inorganic Chemistry

Master Programme In Chemical Engineering, Chemical Engineering With Specialisation In Material Sciences

Activities and Societies: • Worked for the University’s Student Health Services as a representative and instructor, contributing.

Upper Secondary School Diploma, Natural Sciences

University preparing upper secondary school studies with particular focus in the chemical and biological disciplines. "Performance.