Metal Machining
Instance: 2006/2007 - 1S
Cycles of Study/Courses
Teaching language
Portuguese
Objectives
To study the scientific bases of metal cutting and its applications in production engineering problems. To get in-depth knowledge related to machining manufacture and to strengthen mastering of its terminology. To establish the methods and technological parameters, in view of achieving machined parts within the production drawing specifications.
Program
Machining by chip removal; movements and geometrical relationships. Cutting tool nomenclature and geometry. Machine tool selection criteria. Machining operations; turning, milling, drilling and grinding. CNC machine tools; technology and programming (brief reference). Cutting forces and cutting power; shear yield strength in cutting. Chip formation. Modelling of orthogonal cutting. Chip thickness ratio. Shear angle. Deformation and deformation rate. Ernest and Merchant, Lee and Shaffer’s and other models. Material stresses and forces acting on the tool. Energy balance. Three-dimensional cutting. Numerical simulation of metal cutting (brief reference). Tool materials: high speed steels, cemented carbides, ceramics and ultra-hard materials; hard coatings. Wear and tool life. Taylor's law. Relevant factors affecting tool wear. Cutting fluids. Abrasion metal machining. Surface finish. High speed machining (HSM): machining centres, cutting tools and machining strategies. Machining for mould manufacture.
Mandatory literature
Davim, João Paulo;
Princípios da maquinagem. ISBN: 972-40-0878-9
Complementary Bibliography
STENERSON J. and CURRAN K; Computer numerical control, New Jersey Prentice-Hall, 1997
Kief, Hans B.;
Computer Numerical Control. ISBN: 0-07-112673-2
Schulz, Herbert;
Fraisage a grande vitesse des produits métalliques et non métalliques. ISBN: 2-912540-00-3
CHILDS T., MAEKAWA K., OBIKAWA T. and YAMANE Y.; Metal machining theory and applications,, Arnold Publishers, 2000
Trent, E. M.;
Metal cutting. ISBN: 0-408-10856-8
Boothroyd, Geoffrey;
Fundamentals of machining and machine tools. ISBN: 0-8247-7852-9
Shaw, Milton C.;
Metal cutting principles. ISBN: 0-19-859020-2
FERRARESI; Fundamentos da usinagem de metais, Ed. Eduardo Blücher, 1997
Edwards, R.;
Cutting tools. ISBN: 0-901716-48-0
Astakhov, Viktor P.;
Metal cutting mechanics. ISBN: 0-8493-1895-5
McGeough, J. A.;
Advanced methods of machining. ISBN: 0-412-31970-5
Teaching methods and learning activities
In the theoretical/practical sessions the theoretical aspects are exposed by oral presentations, supported by the blackboard or overhead projections, and they will be, whenever possible, practically explored with the execution of application exercises.
Some important technological aspects are observed by video.
Practical work will be done in the shop floor, in small groups, in view to stimulate the know how to do and the creativity for the resolution of the arising problems, eventually in an individual level. Demonstration sessions will take place involving: cutting forces measurement, tool wear assessment and surface finish measurement of the work piece. The written report concerning the practical work is delivered until the end of 11th weak (November 26th) followed by oral presentation and discussion. The students perform also a bibliographic survey, delivered until the end of 7th weak (October 29th) followed by oral presentation and discussion.