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
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 MetalPowder Spray
Plasma Spray
Vapor Deposition

Physical Vapor Deposition

Vacuum Deposition

Sputtering

Chemical Deposition

Ion Platting
Physical Vapor Deposition
Sputtering
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/hou
r
Solution must be
replenished
 Sacrificial anode
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-beamenhanced
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


Electrolytic Cleaning


Physically disturb
contaminants
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.
Types of Measurement and
Instruments Used
Types of Measurement and
Instruments Used
Common Analog Instruments
A caliper gage with a vernier
A vernier
The Micrometer
(c)
(a)
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
Laser Scan Micrometer
Straightness Measurement
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
Fringes on a surface
with two inclinations,
the greater the incline,
the closer the fringes.
Curved fringe
patterns indicate
curvatures on the
workpiece surface
Fringe
pattern
indicating a
scratch on
the 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
Radius Gages
Dial Indicators
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
Photoelectric Digital Length
Measurement


Measures basic dimensions of general
3D parts.
Resolution ranges from 5 - 0.01 µm.
Coordinate-Measuring Machines
(CMM)


Very versatile and capable
of measuring complex
profiles with resolution of
0.25 µm; 10µin at high
speeds.
Larger machines can be
expensive although most
of the touch probe
machines for small shops
cost around $20k
More CMM’s
References






www.brownandsharpe.com
www.faro.com
www.lk-cmm.com
www.renishaw.com
http://www.nd.edu/~manufact/index3.htm
http://www.nd.edu/~manufact/figures.html