Intelligent testing
Case Depth Measurement
Hardness Testing Machines from Indentec.
25 October 2020
Case Depth Hardness
December 2012
Contents
Case Depth Measurement
System Requirements
Testing in Action
Results and Reports
Conclusion
Case Depth Hardness
2
December 2012
Case Depth Measurement
How and Why

Metal components such as gears and constant
velocity joints require hardening to improve
component life

The component is chemically altered then heat
treated so that the outer “case” is hardened but
inner core remains relatively soft

The component is chemically altered then heat
treated so that the outer “case” is hardened but
inner core remains relatively soft

Case hardening increases surface durability
and wear resistance and retains the toughness
of mild steel core

Manufacturers need to know the outer and
inner hardness and the depth to which
hardening has taken place. This is part of the
quality assurance system
Case Depth Hardness
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December 2012
Sample Preparation
Sample preparation is key to Vickers Hardness testing
 A statistically significant number of
components are tested
 The component is cut to reveal the area
of interest
 The surface is polished with a 5-6µ
diamond paste
 Normally small parts of the component,
such as gear teeth, are
metallographically mounted
 The specimens are then tested, normally
with a Vickers hardness tester
 This means potentially tens of thousands
of test points annually and justifies an
automatic system
Case Depth Hardness
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December 2012
Contents
Case Depth Measurement
System Requirements
Testing in Action
Results and Reports
Conclusion
Zwick Roell Hardness Division
5
Automatic System Requirements
Micro and Macro Vickers Testers
.
A fully automated system is comprised of:

A ZHVµ-A or a ZHV30-A hardness tester

ZHVµ.HD Software

Joystick and controller

Automated X-Y Stage

Motorised lead screw (Z-axis)

PC with Windows 7 Operating System
Options:

Metallographic sample mount

Epsom Scanner with Positioning Tool

2.5x lens for mosaic function
A semi-automatic system can also determine case
depth with a manual XY table
Case Depth Hardness
December 2012
Specimen Image Acquisition
Use either scanner or mosaic function
Case Depth Hardness
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December 2012
Metallographic Specimen Mounts
Specimen mounts for single or multiple specimens
The base is fixed to a known position on XY table, drawer is removable so that specimen
image can be scanned.
Base
Small
Medium
Large
Part No
IND07-340
IND07-360
IND07-210
Case Depth Hardness
Drawer
Part No
1 x Ø25-40mm
Select appropriate fitting ring.
IND07-035
1 x Ø50mm
IND07-050
2 x Ø25-40mm
Select appropriate fitting ring.
IND07-360-3
1 x Ø50mm
IND07-360-2
Welded 100 x 55 max
IND07-360-1
8 x 1.5”
IND07-210-1
8 x Ø40mm
IND07-210-2
10 x 1.25”
IND07-210-3
10 x Ø30mm
IND07-210-4
10 x 1”
IND07-210-5
10 x 25mm
IND07-210-6
Welded 70 x 150mm max
IND07-210-7
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December 2012
Contents
Case Depth Measurement
System Requirements
Testing in Action
Results and Reports
Conclusion
Case Depth Hardness
9
December 2012
Automatic Testing in Action
Screen shots from an automatic case depth test
Case Depth Hardness
December 2012
Contents
Case Depth Measurement
Automatic System Requirements
Automatic Testing in Action
Results and Reports
Conclusions
Zwick Roell Hardness Division
11
Case Depth Determination
ZHµ.HD software can display case depth
 Case depths are calculated
automatically by selecting a case
hardness value. A total of four case
depths can be displayed
simultaneously on the same graph.
Case depths are determined in
accordance with ISO 2639
Case Depth Hardness
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December 2012
Case depth results can be exported
Test data can be exported to Excel for incorporation into
customised reports.
Indent
#
1
2
3
4
5
6
7
8
9
10
11
12
Case Depth Hardness
Hardness Vickers Hardness Diag.H
Diag. V
Pos. X
Pos. Y
HV
µm
µm
mm
mm
58.5
664.3 115.18448 121.09744
4
0.401
58.5
664.3 114.71144 121.57048
4
0.901
58.1
655.1 117.54967 120.38789
4
1.401
57.8
649.9 118.73226 120.15137
4
1.901
58.1
655.1 118.25922 119.67833
4
2.401
60.1
700.3 114.47493 115.65752
4
2.901
58.7
668.3 117.54967 118.02271
4
3.401
58
653.8 118.02271 120.15137
4
3.901
56.4
620.1 121.33396 123.22611
4
4.401
48.3
487.6 134.57899 141.20151
4
4.901
28
286.2 189.45128 170.5298
4
5.401
17.1
223.6 204.35193 202.93283
4
5.901
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December 2012
Case Depth Results
Graphical results from Excel showing the depth of case
hardness 580HV
Case Depth Hardness
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December 2012
Contents
Case Depth Measurement
Automatic System Requirements
Automatic Testing in Action
Results and Reports
Conclusions
Case Depth Hardness
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December 2012
Conclusions
Case Depth Determination
 Mosaic or Scanner provides an image of
the component in moments
 Metallographic specimen mount allows
rapid and accurate positioning of the
specimen on the XY stage
 Test point planning is quick and easy
and patterns can be stored and recalled
 Click [Start] and walk away
 Case depth is automatically calculated in
accordance with ISO 2639
 Results can be exported to MS Excel for
bespoke reporting and analysis
Case Depth Hardness
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December 2012