The course aims to provide to the students the ability to choose the proper surface modification treatments according to the different requirements of mechanical components during operation.

In order to achieve this goal, the main surface modification techniques will be described. Among the deposition techniques: Thermal Spray, PVD and CVD and Laser Cladding, and among the thermochemical diffusion treatments: Carburizing and Nitriding.

The main failure mechanisms of materials that mainly originate from the surface will also be briefly dealt with: wear, fatigue, contact fatigue and thermal fatigue.

The course is mainly applicative and will show different industrial applications of the technologies described, thanks also to same meeting with industry professionals and to laboratory sessions.

To stimulate critical capacity in the selection of materials and production technologies, during the course students will be divided into teams, each of which will be entrusted with a specific case taken from industrial examples, which they will have to investigate based on data available in scientific literature and / or provided by the teacher and obtained in the laboratories of the Mechanical  Department of  Politecncio di Milano.

After attending the course and after the final examination, the student will: 

• know the main operational parameters, the resulting microstructures and the mechanical characteristics of the main deposition or surface modification techniques
• know the damage mechanisms in the mechanical components that originate from the surface and be able to identify useful features to mitigate them
• know the measuring instruments used to characterize the tribological behavior of surfaces
• will be able to design an experimental plan to define the adequacy of a surface treatment with respect to the life requirements of the component in use, also thanks to a comparison with the data reported in the literature by different researchers
• will be able to work in a team to achieve a synthetic result derived from several experimental trials and to formulate a summary report to be presented in a public discussion
• will be able to write a technical report

Programme:

At the beginning of the course a resume of the principal coating deposition techniques will be considered:

• Thermal Spray
• Physical Vapor Deposition (PVD)
• Chemical Vapor deposition (CVD)
• Laser Cladding
• Spin Coatings
• Thermochemical diffusion treatments: Carburizing and Nitriding

The main damage phenomena affecting materials originating mainly from the surface will also be briefly presented:

• Wear
• Fatigue
• contact fatigue
• thermal fatigue.

During the course same laboratory session will be organized and the students will be divided in teams; each team will have to examine a specific industrial case by means of:

• pin on disk wear test
• scratch test
• Micro-hardness measurements
• SEM
• GDOES
• Thermal cycles in laboratory furnaces

A background in Metallurgy, chemistry and material science is required

The examination consists of a technical report containing the description of the case study assigned to the group preceded by an exhaustive state of the art derived from the analysis of the scientific literature. It will contain a description of the experimental equipment used and the data obtained in the laboratory sessions.

Each member of the group is asked to give in front of the teacher and the class an oral presentation based on the report that summarizes the experimental work carried out by the group and the main results obtained