Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:1 Environmentally Conscious Design & Manufacturing Class 16: Material Selection Prof. S. M. Pandit

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:2 Agenda Generic automobile materials Engineering materials Properties of materials Guidelines for materials selection Steels, cast iron, alloys, and ceramics

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:3 Generic Automobile Materials

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:4 The Flow of Aluminum Unit: kg

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:5 Materials Use in Automobile Unit: kg

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:6 Design Process Product Function? Need for a device or product Synthesis (Creativity-Ideas) Material selection Product part (prototype) Put Part into Service Redesign Change material? process? Unsatisfactory Evaluate performance Satisfactory

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:7 Engineering Materials Ferrous metals: carbon, alloy, stainless, and tool and die steels Nonferrous metals and alloys: aluminum, magnesium, copper, nickel, titanium, low-melting alloys Plastics: thermoplastics, thermosets, and elastomers Ceramics: glass ceramics, glasses, graphite, and diamond Composite materials: reforced plastics, metal-matrix and ceramic-matrix composites, and honeycomb structures.

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:8 Engineering Materials (cont.) High modulus Abrasion resistant Metals Poor corrosion Resistance Ceramics brittle Glasses Brittle Elastomers creep at low temp Polymers creep at low temp Composites Corrosion resistant Low modulus High strength High strength, Moderate modulus, High ductility

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:9 Properties of Materials Mechanical properties:strength, toughness, ductility, hardness, elasticity, fatigue, and creep Physical properties: density, thermal expansion, conductivity, specific heat, melting point, and electrical and magnetic properties Chemical properties:oxidation, corrosion, toxicity, and flammability Manufacturing properties: castability, formability, machinability, weldability, and hardenability by heat treatment.

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:10 Properties of Materials (cont.) Production Composition Recycling Energy Effluents Resource depletion Environmental Aspects

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:11 Guidelines for Materials Selection Traditional guidelines for materials selection: Desired mechanical, physical, and chemical properties Shapes of commercially available materials Reliability of supply Cost of materials and processing

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:12 Guidelines for Materials Selection (Cont.) Guidelines for materials selection from the ECDM viewpoint: Choose abundant, non-toxic, nonregulated materials Choose materials familiar to nature Choose easily recycled materials Minimize environmental impact without loss of product quality

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:13 Low-Impact Materials  Non-hazardous materials  Non-exhaustable/renewable materials  Low-energy content materials  Recycled and recyclable materials

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:14 Energy Aspects Energy to mine raw materials Energy to extract and refine ore Energy to from product Energy to ship product Energy to use product Energy to disposal of product

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:15  Part is remanufacturable – Example: starter, transmission  Steel, aluminum, lead, and copper have good recycling records.  Organic material for energy recovery, that cannot be recycled. Example: Tires, rubber in hoses.  Inorganic material with no known technology for recycling. Material Recyclability

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:16 Types of recycled material –home scrap –pre-consumer –post-consumer Design considerations –ease of disassembly –material identification –simplification and parts consolidation –material selection and compatibility Material Life Extension

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:17 Improvements of Existing Products Substitution (water based coatings instead of volatile organic compounds) Reformulation (e.g., unleaded gasoline is a reformulation of the leaded variety) Elimination

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:18 Reduced Material Intensiveness Dematerialization - Less materials means less consumption, saves energy and money. Shared use of product Integration of functions Functional optimization of product and components

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:19 Weight reductions reduce energy needed to move the product. Avoid over-dimensioning the product via good design Reduction in volume (space required for transport and storage) Reduction of Material Usage

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:20 Example (Xerox) Source: Calkin, P., 1998

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:21 The Results of Efforts Reduced solid waste generation by 73 percent Increased the factory recycle rate by 141 percent Reduced releases to the environment by 94 percent Realized over $ 200 million in annual savings

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:22 Steels Plain carbon steels Low-carbon steel (0.02% - 0.3%C), used for manufacturing bolts and nuts, bars and rods Medium-carbon steel (0.3% %C), used to harden tools such as hammers, screw drivers, and wrenches. High-carbon steel (0.6 % - 1.5%C), for edge cutting tools such as punches, dies, taps, and reamers. Alloy steels Addition of alloying elements (Cr, Mn, Mo, Ni, T, V) improves mechanical properties of steels

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:23 Cast Iron Alloy of iron and carbon (1.7%-4.5%C) Gray cast iron, used in machine tool, automotive, and other industries White cast iron, used for the production of malleable iron casting Chilled cast iron, used for products with wear-resisting surface Alloy cast iron, used in automotive engine, brake, and other systems, machine tool casting, etc. Malleable iron castings, used in industrial applications that require a highly machinable metal, great strength ductility and resistance to shock.

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:24 Aluminum and its Alloy Properties: High strength-to-weight ratio Resistance to corrosion High thermal and electrical conductivity nontoxicity, ease of recycling reflectivity, ease of machinability Uses: Con and foil Construction (building etc.) Transportation (aircraft, automobile, etc.) Electrical conductors, and appliances

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:25 Nonferrous Alloys Copper-based alloys (ex. Brasses and bronzes) - good strength, hardness, conductivity. Aluminum-based alloys - increased tensile strength, weldability, ductility Nickel-based alloys - high strength and corrosion resistance Zinc-based alloys - good corrosion resistance, strength, and ductility

Environmentally Conscious Design & Manufacturing (ME592) Date: April 10, 2000 Slide:26 Ceramics Types Oxide ceramics, carbides, nitrides, cermets, sialon General properties Brittle, high strength, high hardness, low toughness, low density, low thermal expansion, and low thermal and electrical conductivity Applications Automobile components, electronics, cutting tools, fiber optics