Today, there is an increasing use of polymeric and ceramic materials. Despite this, the metallic alloys are by far the most used class of materials in the manufacturing of mechanical components. There is a huge number of different alloys with different properties and new ones are continuously developed and put on market. Simultaneously a lot of manufacturing processes are able to produce complex components with the desired properties. Nevertheless, the need for new techniques is always increasing. In this scenario, the importance to put a big effort in the research for new alloys and new processing routes can be easily understood. Focusing our attention, in the framework of this short course on manufacturing processes the first issue that should be addressed is: what is a manufacturing process?

Looking in the Cambridge Dictionary it can be found that the manufacturing is defined as “the business of producing goods in large numbers”, and the word process it can be defined as: “a method of producing goods in a factory by treating natural substances” or “a series of actions that you take in order to achieve a result”. Trying to adapt these definitions to a specific manufacturing process, for instance rolling or deep drawing, it can be stated that a manufacturing process is a system of external actions (that can be mechanical, thermic, electrical or chemical) that are applied on a material to change its shape and properties to obtain the desired part. Under this light it is clear the role of the researcher in manufacturing: to conceive and develop new systems of external actions and to better set the values of the external actions (that can be read as: to choose the process parameters) for already existing processes when introducing new alloys. Doing this a central point is to understand the laws that rule the behaviour of the material, in other words aiming to define a system of external actions that will produce the desired changes (both in terms of shape and properties) in the material is mandatory know how the material will behave when subjected to these actions. The behaviour of a certain alloy is mainly influenced by both “internal” factors and “contour” conditions. The former are: chemical composition, lattice structure, internal defects, precipitates, grain structure or microstructure; the latter is mainly temperature.

In this short course, the attention will be focused on the relationship among microstructure, manufacturing processes and mechanical properties. It will be described how different processing conditions will produce different microstructures that will lead to different properties of the manufactured product, moreover it will be discussed how, depending on the microstructure of the base material, the processing conditions should be accordingly set. In more details this course will be related to aerospace alloys, mainly titanium and aluminium, and to processing techniques, both mass additive and mass conserving, used in the production of aeronautic components.

Students will be familiar with the different microstructures produced by different processing routes in aluminum, titanium and inconel alloys. You will also have an idea to the influence of the initial microstructure on the material processing.

Asistencia obligatoria

Suggested readings:

• Elements of Metallurgy and Engineering Alloys, Flake Campbell, ASM International 2008
• Physical Metallurgy, Cahn and Haasen
• Titanium: a technical guide, Donachie, ASM International
• Titanium Handbook, ASM International
• Aluminum Handbook, ASM International
• The website of professor Sir Bhadeshia - http://www.phase-trans.msm.cam.ac.uk/Bhadeshia.html - for steel metallurgy