Metallographic Etchants
CAUTION: Safety is very important when etching.
Be sure to wear the appropriate protective clothing and observe all
Aluminimum alloys
High carbon Steel
Brasses and Bronzes
Stainless Steel
Cast Iron
Tin Alloys
Copper Alloys
Zinc Alloys
Low carbon Steel
Ceramics
The most commonly used etchants
Etchant
Composition
Conc.
Conditions
Comments
Kalling's
No. 1
Distilled water
CuCl2
Hydrochloric
acid
Ethanol
33 ml
1.5
gram
s
33 ml
33 ml
For etching
Immersion
martensitic stainless
etching at 20
steels. Martensite will
Degrees
be dark and the ferrite
Celcius
will be colored.
Kalling's
No. 2
CuCl2
Hydrochloric
acid
Ethanol
5 grams
100
ml
100
ml
Immersion
etching at 20
Degrees
Celcius
For etching duplex
stainless steels and
Ni-Cu alloys and
superalloys.
Kellers
Etch
Distilled water
Nitric acid
Hydrochloric
acid
Hydrofluoric
acid
190 ml
5 ml
3 ml
2 ml
10-30
second
immersion.
Use only
Fresh
etchant
Excellent for
aluminum and alloys
immersion for 10-20
seconds ; titanium
alloys immersion for
10-20 seconds.
Etchant
Composition
Conc.
Kroll’s
Reagent
Distilled water
92 ml
Nitric acid
6 ml
Hydrofluoric
2 ml
acid
Conditions Comments
15 secs
Excellent for titanium
and alloys. Swab
specimen up to 20
seconds.
Most common etchant
for Fe, carbon and
alloys steels and cast
Seconds
iron - Immerse sample
to
up from seconds to
minutes minutes; Mn-Fe, MnNi,
Mn-Cu, Mn-Co alloys–
immersion up to a few
minutes.
Nital
Ethanol
Nitric acid
100 ml
1-10
ml
Marble's
Reagent
CuSO4
Hydrochlori
c acid
Water
For etching Ni, Ni-Cu
Immerse
10 grams
and Ni-Fe alloys and
or swab
50 ml
superalloys. Add a
for 5-60
50 ml
few drops of H2SO4
secs.
to increase activity.
Etchant
Compos
ition
K3Fe
(N)6
Murakami's
KOH
Water
Picral
Ethano
Picric
acid
Glycerol
Vilella’s
HNO3
Reagent
HCl
Conc.
Conditions
10 grams
10
grams
100 ml
Pre-mix KOH
and water
Before
Adding
K3Fe(CN)6
100 ml
2-4 grams
Seconds to
minutes
45 ml
15 ml
30 ml
Seconds to
minutes
Do not let
etchant
crystallize
or dry –
explosive
Comments
Cr and alloys (use fresh and
immerse); iron and steels
reveals carbides; Mo and
alloys uses fresh and
immerse; Ni-Cu alloys for
alpha phases use at 75
Celcius; W and alloys use
fresh and immerse; WC-Co
and complex sintered
carbides.
Recommended for
microstructures containing
ferrite and carbide.
Good for ferrite-carbide
structures (tempered
martensite) in iron and steel
Guide to Acid Concentrations
Acid / Base
Specific
gravity
Concentration
Nitric (HNO3)
1.4
68-70%
Hydrofluoric (HF)
-
40%
Hydrochloric (HCl)
-
37-38%
Ammonium Hydroxide (NH4OH)
-
35%
Specimen and Mount Holders
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Specially Designed
Specimen Holders For SEM:
The specimen holders are
designed to improve
productivity and allow one to
view more than one sample at
a time. This saves pump down
time, keep chamber cleaner
and get more work done. All
mounts are machined from
solid aluminum and come with
spring clips/or setscrews to
hold specimens securely. All
mounts are made to fit onto the
stage and are designed to fit
through all standard specimen
exchange ports, and have a
center-threaded port to accept
the Adapter Pins that fits SEM
instrument. Three different
types of pin adapters, which
are threaded and ready to
screw on to the base of the
holders are available.
Adapter A: Overall measurement: 28mm
long x 3.1mm diameter (step-up portion is
6.25mm L x 4.8mm diameter),
Adapter B: Overall measurement: 28mm
long x 6mm diameter,
Adapter C: Overall measurement: 34.5mm
long x 16mm diameter
All adapters have a threaded portion 5mm
in length.
Universal SEM Sample Holder
To hold almost any sample from 3mm to
29mm in diameter plus various odd
shaped samples, with the dimensions not
greater than 29mm. The samples are
easily inserted or removed from the
holder. The holder is made from
aluminum and is with four removable
sample arms so that it can hold very small
samples as well, and it provides good
electrical contact to the stage.
The standard base measures: 48mm x
42mm x 12mm Thick.
.
Vertical Mount for Thin Samples;
Flat Base
This is designed to hold thin samples
vertically in the SEM or any
microscope. It is 25mm in diameter and
10mm thick. Each of the two loader
jaws can hold up to 3mm thick
samples. The spring loader keeps thin
samples vertical so that cross sections
can be studied. This holder is very
useful for cross sections of silicon
wafers or multilayer capicators.
.
Multi Pin Holder
The Multi Pin Holder is designed to
save time. It accommodates 3 or 5
of ½" dia.(12.5mm) surface, 1/8"
dia. (3.1 75910 Specimen Holders
For SEM 10-14 mm) pin.
ISI DS 130 and 150 First Stage
Sample Mounts
It is 10mm in diameter, 5mm high,
copper sample holder to fit in the
first stage of the ISI DS 130 and
150 SEM's. The inner cylinder is
height adjustable so that one can
adjust the sample to the correct
working distance.
SEM Sample Holder Set
For convenience a SEM Sample
Holder Set to fill all needs is
available. The set consists of one
universal holder, one vertical mount
holder for thin samples, one 3-pin
and one 5-pin configuration holder
with a key for the set screw all in a
finely finished wood box.
Pin Mount Stub Adapters
Made from aluminum, used to
adapt 1/8" (3.1mm) pin
diameter SEM stubs.
Available in 10, 15, 16mm
diameter as well.
Cross Sectional Holder
Made from non-magnetic
stainless steel with 3.1mm
(1/8") diameter pin and
adjustable angle turn-screw.
Just insert specimens edgeon and observe the cross
section directly
Four-Pin Stub Holder
It accommodates four pin
type, up to 12.5 (1/2")
surface specimen stubs,
with 1/8" (3.1mm)
diameter pin.
Five 10mm Stub Holder
Accommodates five 10mm
diameter specimen stubs, with
1/8" (3.1mm) diameter pin
Thin Sample Holder
Ideal for examination cross section of
thin samples, such as wafers, multi-layer
of capacitors, plastics, metals, etc.
½" diameter (12.7mm), 1/8" (3.1mm)dia.
pin (3.1mm) with split openings up to ¼"
(6.4mm). Available with either 8mm
(5/16") pin height or 15mm (9/16") pin
height.
For ISI, JEOL, TOPCON: Double set
screw for a secure holding of the
specimen during observation.
15mm(9/16")(dia). x 10mm(3/8")(H),
6.4mm(1/4") split.
• METALLURGICAL LABORATORY TESTING
Metallurgical labs stocked with state-of-the-art of equipment that allows
to help in materials selection, characterization, component and process
design, qualification, failure analysis, and many other services.
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Specimen Preparation
Automatic grinding and polishing equipment
Abrasive cut-off wheels
Epoxy and cold mount
Large section specimen (up to 9 in.) metallographic preparation
Acid and electrolytic polishing/etching techniques
Specialized sectioning capability
Etching techniques for most common materials
Removal of rust and scale prior to failure analysis
Microstructural Analysis
Optical microscopes: magnification up to 2000x with oil immersion
Scanning Electron Microscope
Cambridge Stereoscan 360
Windowless EDS capability for microstructural chemical analysis
• Image Analysis
• Micro- and macro-digital photographic capability
• Quantitative image analysis for:
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Area fraction
Feature measurement
Modularity
Grain size
Size distribution
Inclusion rating
Crack length
• Software-based weld profile measurement Conventional
& digital macrophotograph capability
• Materials Testing
• Hardness testing (Rockwell A, B, C)
• Microhardness testing (Vickers, Knoop)
• Magne-gage for ferrite measurement
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Weldability Testing
Gleeble 1000 Thermal/Mechanical Simulator
Universal Varestraint
Oberlikon-Yanaco Hydrogen Analyzer with high-temperature
measurement capability
Heat Treatment
3-cubic ft. convection furnace
12-cubic ft. convection furnace
9-cubic ft. oven
Nondestructive Evaluation (NDE)
Ultrasonic immersion testing
Ultrasonic contact testing
Eddy current testing
Meandering Winding Magnetometer (MWM)
Surface cleanliness monitor (Optical Stimulated Electron Emission
[OSEE])
Magnetic particle testing
Penetrant testing
Baroscope and visual inspection
Radiography
Thermography
•
STANDARD TESTING SERVICES
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Tensile Bend Fatigue
Charpy impact Fracture toughness (CTOD, J&K)
Heat treatment services (stress relief, normalizing ageing)
Weld cracking sensitivity tests (WIC, Y-groove, CTS, GBOP)
Diffusible hydrogen measurement (Mercury and gas chromatography)
Gleeble Thermo-mechanical simulator
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Weld simulation CCT curves
Process simulation
Thermal/mechanical simulation
Weldability (Varestraint, Sigamajig)
Microstructural characterization
• Optical Hardness Feature quantification
• Weld procedure qualification
• Residual stress measurements (blind-whole method)
Digital image analysis SEM with
EDS capability
Experimental stress analysis (strain gauging services)
High temperature testing up to 1200°C
Expert failure analysis
Welding services (PQR, test plate fabrication, etc.)