Manufacturing Technology: Introduction to Processes

Manufacturing Processes

• Two or more separate parts are joined to form a new entity through assembly processes.

Solidification Processes

• Starting material is heated sufficiently to transform it into a liquid or highly plastic state.
• Examples: casting for metals, molding for plastics.
• Casting process:
  • Mold: contains a cavity that determines the shape of the component.
  • Mold materials: sand, plaster, ceramic, and metals.
  • Types of molds: open mold, closed mold, expendable mold (destroyed after single use), and permanent mold (can be used multiple times).

Deformation Processes

• Starting work-part is shaped by application of forces that exceed the yield strength of the material.
• Examples: forging, extrusion, and rolling.

Material Removal Processes

• Excess material is removed from the starting workpiece to achieve the desired geometry.
• Examples: machining (turning, drilling, and milling), grinding, and non-traditional processes.

Assembly Operations

• Two or more separate parts are joined to form a new entity.
• Types of assembly operations:
  • Joining processes: create a permanent joint (e.g., welding, brazing, soldering, and adhesive bonding).
  • Mechanical assembly: fastening by mechanical methods (e.g., use of screws, bolts, nuts, and other threaded fasteners; press fitting, expansion fits).

Property-Enhancing Processes

• Performed to improve mechanical or physical properties of the work material.
• Part shape is not altered, except unintentionally.
• Examples: heat treatment of metals and glasses, sintering of powdered metals and ceramics.

Surface Processing

• Cleaning: chemical and mechanical processes to remove dirt, oil, and other contaminants from the surface.
• Surface treatments: mechanical working (e.g., sand blasting) and physical processes (e.g., diffusion).
• Coating and thin film deposition: coating exterior surface of the workpart.

Developing a Manufacturing Process

• Understand function/geometry properties: mechanical, electrical, thermal, magnetic, optical, and deteriorative.
• Identify candidate material(s) considering structure, composition, and required processing.
• Material and geometry compatibility are crucial considerations.

Characterizing Processes

• Quality: dimensional (bulk and surface) and properties (bulk and surface).
• Economics: cycle time, materials utilization, and cost.
• Flexibility: tooling development, setup time, and cycle time.

Materials in Manufacturing

• Most engineering materials can be classified into one of four basic categories.

Manufacturing Technology

• Definition: derived from the Latin word manufactus, meaning "hand-made".
• Practical definition: process of converting or processing raw materials into usable products.
• Purpose: transformation of materials into items of greater value by means of one or more processing and/or assembly operations.