Oğuzhan Paçal, 030070031, 6th week

Design for recycling
Green design anticipates the possible adverse enviromental impact of materials, products, and processes, so that it can be taken into account at the earliest stages of design and production. The main objectives are to prevent pollution at the source and to strongly promote recycling and reuse instead of disposal. These goals have led to the concept of design for recycling (DFR)
(Serope Kalpakjian, Steven R. Schmid, Manufacturing Engineering and Technology,p. 33)

Artificial Aging
The properties of an age-hardenable alloy depend on both aging temperature and aging time. For example at 260°C, diffusion in the Al-4% Cu alloy is rapid, and precipitates quickly form. The strength reaches a maximum after less than 0.1 h exposure. At 190°C which is a typical aging tepmerature for many aluminum alloys, a longer time is required to produce the optimum strength. Aging at either 190°C or 260°C is called artificial aging because the alloy is heated to produce precipitation.However the peak strength is relatively lower than natural aging.
(Donald R. Askeland, The Science and Engineering of Materials, p.307-308)

Buckling
When a column is under F axial load it stays put. If we increase the force over time, there will be a critical load where the column will bend from the axis this is called buckling.There are 4 types of bucking
Column(Axial) Buckling, Radial Buckling, Pressure caused Buckling and Torsional Buckling.
Think of a column of a material where E is elasticity modulus and I is the moment of inertia, L is the lenght of column. There is an equation between F and the properties of material which tells that there is a critical F load of buckling.

F=(pi)^2*E*I/L^2

(Prof Dr Mustafa Savcı Prof Dr Alaeddin Arpacı, Mukavemet, p.299)

Process Selection Charts
Process Selection Charts summarize material properties and process attributes.The material charts map the areas of property space occupied by each material class. They can be used in two ways

• to retrieve approximate values for material properties
• to select materials which have prescribed property profiles

The collection of process charts, similarly, can be used as a data source or as a selection tool.Sequental application of several charts allows several design goals to be met simultaneously.The best way to tackle selection problems is to work directly on the appropriate charts.
(Michael F. ASHBY, Materials Selection in Mechanical Design, p. 413)