650 likes | 1.29k Views
Surface Treatments & Engineering Metrology & Instrumentation Group 8 ME 260 Fall 2005 11/30/05. Kurt Sorenson Derek Benavidez Colin Evans Steven Best. Introduction. Surface Treatments Why? Types Cleaning Mechanical Measurements Standards Types Dimensioning.
E N D
Surface Treatments & Engineering Metrology & InstrumentationGroup 8ME 260Fall 200511/30/05 Kurt Sorenson Derek Benavidez Colin Evans Steven Best
Introduction • Surface Treatments • Why? • Types • Cleaning • Mechanical Measurements • Standards • Types • Dimensioning
Why use a surface treatment? • Improves durability • Controls Friction • Reduces Adhesion
Why use surface treatment? (cont) • Improves Lubrication • Rebuild Surfaces • Aesthetics
Types of Treatments • Mechanical Surface Treatments • Mechanical Plating & Cladding • Case Hardening • Thermal Spraying • Vapor Deposition • Laser Treatments
Mechanical Surface Treatments • Peening • Shot Peening • Laser Shot Peening • Water-jet Peening • Ultrasonic Peening • Roller Burnishing • Explosive Hardening
Mechanical Plating & Cladding • Mechanical Plating • Cladding • Laser Cladding
Case Hardening and Hard Facing • Case Hardening • Hard Facing • Spark Hardening
Thermal Spraying • Combustion Spraying • Thermal Wire Spray • Thermal Metal-Powder Spray • Plasma Spray
Vapor Deposition • Physical Vapor Deposition • Vacuum Deposition • Sputtering • Chemical Deposition • Ion Platting
Chemical Vapor Deposition • Thermochemical Process • Cutting Tools • Thicker • Tedious
Ion Implantation & Diffusion Coating • Particulates penetrate substrate • Modifies surface properties • Increases hardness • Improves durability • Masking capability
Laser Treatments • Heating • Melting • Vaporization • Peening
Electroplating, Electroless Plating,and Electroforming • Electroplating • Workpiece (cathode) is plated with other metal (anode) through a water-based electrolytic solution • A SLOW Process!!! • 75 micrometers/hour • Solution must be replenished • Sacrificial anode • Additional salts of metal
Electroplating, Electroless Plating,and Electroforming • Operation Sequence • Chemical Cleaning • Acid Bath • Application of a Base Coat (Optional) • Final Electroplating • Rinse Tanks • Common Plating Metals • Nickel • Cadmium, Copper • Tin, Zinc
Electroplating, Electroless Plating,and Electroforming • Electroless Plating • Chemical Reaction • More Expensive $$ • Uniform Thickness • Electroforming • Metal-fabrication • Metal electrodeposited on a mandrel
Conversion Coatings • Anodizing- • The workpiece is the anode in an electrolytic cell • Coloring- • Alters color of metals, alloys, and ceramics • Conversion of surfaces into chemical compounds: oxides, chromates, and phosphates
Hot Dipping • Workpiece is dipped into molten metal • Zinc- galvanized-steel sheet • Tin- food containers • Hot-dipped Galvanizing line
Porcelain Enameling; Ceramic and Organic Coatings • Enamels- fuse a coating material by heating to 425 to 1000. • Ceramic coatings- Intense temp applied • Organic coatings- Wide range of properties: flexability, durability, color, texture…
Diamond Coating and Diamond-Like Carbon • Techniques • Chemical vapor deposition • Plasma-assisted vapor deposition • Ion-beam-enhanced deposition • Diamond Properties • Hardness, wear resistance, thermal conductivity
Surface Texturing & Painting • Texturing Techniques • Etching • Electric Arcs • Lasers • Atomic oxygen • Paint Classification • Enamels • Lacquers • Water-based paints
Cleaning of Surfaces • 3 types • Mechanical Cleaning • Physically disturb contaminants • Electrolytic Cleaning • Abrasive bubbles aid in contaminant removal • Chemical Cleaning • Solution • Saponification • Emulsification • Dispersion • Aggregation
Engineering Metrology and Instrumentation Metrology refers to the measurement of any type of dimensions (length, thickness, diameter, angle, etc.) Focus on Dimensional Tolerance (functionality, interchangeability, cost)
Describing Quality of Instruments • Resolution- the smallest difference in dimensions that an instrument can detect. • Precision- the instruments ability to give repeated measurements (thermal expansion affects precision, standard measuring temperature is 200 C). • Accuracy- The ability of a measurement to match the actual value of the quantity being measured.
Common Analog Instruments A caliper gage with a vernier A vernier
(c) (a) The Micrometer Analog Micrometer Digital Micrometer
Angle-Measuring Instruments Bevel Protractor Vernier for angular measurement
Angle-Measuring Instruments Sine Bar Gage blocks are added until the top surface is parallel to the surface plate. The angle is calculated using trig. relationships.
Comparative Length Measurement Multiple-Dimension Gaging
Electronic Gages Measuring Bore Diameters Vertical Length Mesauring Instrument
Interferometry for Measuring Flatness Optical Flat is a glass disk or fused-quartz disk with parallel flat surfaces. A light beam with one wavelength is aimed at the surface at an angle and splits into two beams. The number of fringes relates the distance between part and flat.
Interferometry for Measuring Shaped or Textured Surfaces Fringe pattern indicating a scratch on the surface. Fringes on a surface with two inclinations, the greater the incline, the closer the fringes. Curved fringe patterns indicate curvatures on the workpiece surface
Measuring Roundness Measuring roundness using V-block and dial indicator
Measuring Roundness Part supported on centers and rotated Circular tracing, with part being rotated on a vertical axis
Measuring Profiles Dial Indicators Radius Gages
Measuring Profiles Gear-Tooth Caliper Gear-Tooth Micrometer
Horizontal-Beam Contour Projector Image is projected on screen at magnification of 100X or higher. Measurements made directly on screen.
Gages Plug gages for holes Ring gages for round rods GO means smaller than desired size and should fit perfectly, if NOT GO gage also fits then tolerance is not met.
Gages Snap Gage with adjustable anvils
Gages Pneumatic Gage
Modern Measuring Instruments and Machines Electronic gauges Laser Micrometers Laser Interferometry Photoelectric digital length measurement Coordinate-measuring machines (CMM)
Electronic Gauges • Determine travel length by changes in electrical resistance, inductance, or capacitance. • A commonly used E-Gauge is the linear-variable differential transformer (LVDT) • Generally use a very accurate specified probe tip.
Laser Micrometers • A laser beam scans a workpiece, generally at a rate of 350 times per second. • Generally capable of resolutionsas high as 0.125 µm (5 µin).
Laser Interferometry • Used primarily to check and calibrate machine tools. • Also are used to compensate for positioning errors in CMM and CNC machines