M10

• Materials Selection


  • What selection criteria are important to meet the requirements of product?
  • How do designers select the best material?
  • What is an ideal material?
• In materials selection, COMPROMISE is the rule not the exception
• Materials Selection


  • Material science
  • Engineering mechanics
  • Engineering design
  • MANUFACTURING
  • Life-cycle concerns
  • Fundamental laws
  • Material-component interactions
  • Quality
  • Reliability
  • Cost
• Roles of Engineers in Manufacturing

  • Manufacturing Engineers
  • Design Engineers
  • Materials Engineers
  • Materials Scientists
• Manufacturing Engineers


  Select and coordinate specific processes and equipment to be used
• Design Engineers


  Select and specify the materials to be used in order to meet the requirements. Design the machines and equipment used in manufacturing
• Materials Engineers


  Devote their major efforts toward developing new and better materials for use in commercial products
• Materials Scientists


  Study how the structure of materials relates to their properties
• Selection Tools and Factors

  • Availability
  • Economics
  • Properties
• Availability


  Material must be available at a reasonable cost and in the desired form (if not available in the desired state, the material should be convertible to the desired form)
• Economics


  Cost of materials and processing must be considered
• Properties


  Materials performance characteristics
• Characteristics of an Ideal Material

  • Endless supply and readily available
  • Cheap to refine and produce
  • Energy efficient
  • Strong, stiff, and dimensionally stable at all temperatures
  • Lightweight
  • Corrosion resistant
  • No harmful effects on the environment or people
  • Biodegradable
  • Numerous secondary uses
• Materials Selection Process


  1. Pick Application

  2. Determine required properties (mechanical, electrical, thermal, magnetic, optical, deteriorative)

  3. Identify candidate material/s, structure, composition

  4. Identify required processing: casting, sintering, vapor deposition, doping, forming, joining, annealing, etc.

  5. Additional selection criteria
• Additional selection criteria


  • Existing specifications
  • Availability
  • Processibility
  • Near-net-shape production
  • Quality and performance
  • Consumer acceptance
  • Design for assembly
• Basic Approaches to Final Materials Selection

  • Minimum investment and high maintenance
  • High investment and low maintenance
  • Optimum investment and maintenance
• The number of materials available is large and constantly increasing
• Domestic and foreign competitions increasingly require product reevaluation
• Service requirements and consumer demands for reliability as well as function have become more severe
• The material has a direct relationship to the appearance of the product and its sales appeal
• The material dictates what processing must be used in order to manufacture the product
• Failure of products can result in very costly litigation and damages due to strict and comprehensive product-liability laws
• At one time or another, we will be faced with a design problem involving materials
• The problem will be selecting the right material with the desired properties for a specified application
• Criteria for selection of the final material

  • In-service conditions
  • Performance
  • Cost
• It is up to the engineer/scientist to decide after having considered all of the factors involved
• Material Classifications


  • Metals
  • Ceramics
  • Polymers
  • Composites
  • Biomaterials
  • Semiconductors
• Shoe requirements: Stiff sole for power transfer, but flexible enough to allow natural foot movement. Good grip for traction. Rigid material and snug fit for lateral support. Padded insole for comfort and arch support. Lightweight.
• Bicycle requirements: Lightweight, Stiff and strong, Durable componentry
• Bicycle materials


  • 7000 series aircraft-grade aluminum alloy (frame)
  • Carbon-fiber (fork legs, seatpost)
  • Steel alloy (fork steerer)
  • Cold-forged aluminum (components)
  • Aluminum alloy (rims)
  • High-tensile steel (spokes)
  • Aluminum alloy (handlebar)
• Bicycle materials (high-end)


  • Monocoque carbon fiber (frame, integrated seatpost)
  • Full carbon fiber (fork)
  • Cold-forged aluminum, carbon fiber (components)
  • Carbon fiber (rims, handlebar)
• Weight: 8.84 kg (19.5 lbs)
• Weight: 6.8 kg (15 lbs)
• The Content of this Presentation came from the Presentation of Engr. Emmanuel C. Guevara for Material Science and Engineering