9
10
energy. Accordingly, the roughness of sample testing points on the
surface Ra≤ 1.6.
2) The shape of sample surface
Leeb testing principle demands the velocity of rebound and impact
are on the same line, because the impact body is moving in a metal
tube. Even if the velocity of rebound and impact are not on the same
line, it also can show hardness for sure, but the impact body would
collide with tube wall when it rebounds, which will affect the velocity
of rebound. Therefore, a greater error is on test accuracy. When the
radius of curvature of the testing sample surface is smaller, the
solution is the use of suitable variant supporting circle. If users
require special supporting circle, we can contribute to design and
process.
3) The weight of the sample
If the sample weight must be larger than or equal to 5kg, and not
easily sway. If the sample weight were less, the sample would need
proper treatment (It is necessary to increase the supporting or
mounting through coupling compress on larger weight testing stand),
and the testing results can be achieved in accuracy. There should be
a certain area at the testing points (the area required to meet a set of
testing points) and no vibration or shaking. If the weight is not
enough, users must be as much as possible reduce the jitter and
sloshing by the methods of increasing supporting, coupling and
compressing. And supporting device should avoid shock.
4) The sample stability
Any effective tests need to minimize possible interference from
outside; it's more important to dynamic measure such as Leeb
hardness test. Therefore, measuring only allowed in stable hardness
testing system. If it's likely to lead to sample movement in the tests,
users should fix it before testing.
Factors Affection Accuracy
Incorrect operation or improper testing conditions would have
serious impact on testing accuracy. Following is several common
factors effect the accuracy of testing for the use of reference:
1) Roughness of sample surface
When the impact body impact on the sample, a small pit would arise
on the sample surface, so at the same time, should finish the surface
of the sample. The more roughness, the less consumption of impact
energy whereas the less roughness, the more consumption of impact
Materials
HLD
HV
HRC
HRB
HS
Tensile
strength(Mpa)
Steel & cast steel
300-900
81-955
20-68
38 -100
Tool steel
20-67
Stainless steel
85-802
47-101
Cast iron
Cast aluminum alloy
Brass
Bronze
Copper
300-840
300-800
360-650
170-570
200-550
300-700
200-960
80-898
HB
81-654
85-655
93-334
19-164
85-655
93-334
19-164
40-173
60-290
45-315
23-84
13-95
32 -100
375 -2639
Measuring And Conversion Range
Main unit
Impact device D
Hardness test block
Small support ring
Cleaning brush
1pc
1pc
1pc
1pc
1pc
Support rings
refer to our catalogue
Standard Delivery
Optional Accessory
Wireless printer
ISH-DS-PRINTER
