where expertise comes together - since 1996 -

The Largest Open Access Portal of Nondestructive Testing (NDT)

Conference Proceedings, Articles, News, Exhibition, Forum, Network and more

where expertise comes together
- since 1996 -

PBP Optel sp. z o.o.
Weare searching new ways - in ultrasonic techniques- in creation of new productsUltrasonic instruments - Ultrasonic Testing Card
297 views
Technical Discussions
arun kumar
arun kumar
07:37 Dec-11-2002
four point probe resistivity measurement

the following queries are regarding the four point probes used for material detection


can the four point probes be used for thick plates, large drums? if yes what is the level of accuracy? what are the correction factors to be used for differen dimensions?


 
 Reply 
 
Sean S. Franklin
Sean S. Franklin
08:31 Dec-11-2002
Re: four point probe resistivity measurement
:
Aarun,

Yes, the four point probe resistivity measurement or the MDT Automation M100A Metal Inspector can be used to measure various thick geometrical samples.

Firstly, probes are identified by the center spacing of the two adjacent pins (pins 2 and 3, two inner most pins). This spacing is measured in inches and converted to thousandths of an inch (mil). Therefore, a probe that has 0.100 (2.54mm) inch spacing between the pins is called a 100 mil probe.

The first consideration in selecting a probe is the type of measurement you plan to make. If the measurement of absolute resistivity is of primary importance, then the probe should be much smaller than the sample size. For relative resistivity measurements, you can choose any probe if you establish a reference resistivity against which measurements can be compared.

Finally, the volume of the sample bound by the probe is important for thickness measurements. Current penetration is approximately one and a half (1-1/2) times the probe pin spacing. For example, the 100 mil probe can be used for applications to a depth of 150 mil, 500 mil probes up to a depth of 750 mil, and so on. The level of accuracy is within +/- 3% without a fixture and 1% with a fixture. The fixture is designed to position and stabilize the probe to the sample surface.

For additional information and literature, please contact Sean Franklin @ 609-716-4088 or Sfranklin@NDTAutomation.com

: the following queries are regarding the four point probes used for material detection
.
:
: can the four point probes be used for thick plates, large drums? if yes what is the level of accuracy? what are the correction factors to be used for differen dimensions?
.



 
 Reply 
 

Product Spotlight

Varex Imaging Large Field of View (FOV) Digital Detector Arrays (DDAs)

A larger FOV DDA can reduce the space and volume of the X-ray inspection system on the factory floor
...
, enable faster scanning times, better throughput and better resolution images at a lower dose. Customers can also save time and money. With these benefits in mind, Varex Imaging has designed a family of large FOV detectors (4343HE, XRD 1611, 4343DX-I, 4343CT) for our industrial imaging customers.
>

Teletest Focus+

Teletest Focus+ electronics have superior capabilities than rivals on the market. Beyond the usual
...
test features, Focus+ has 24 transmit channels and 24 receive channels, with an additional on-board switching capabilities. The instrument's frequency range is 10–300 kHz.
>

iProbe - USB Phased Array Probe

Turn your PC, Laptop or Tablet into a powerful 32:64 Phased Array system with our USB powered Phas
...
ed Array iProbe and inspection software package. Perform affordable weld inspection and corrosion mapping inspections with this powerful but small system. The probe has a 100V pulser, 8K PRF, dual axis encoder input and achieves outstanding signal quality.
>

IntraPhase Athena Phased Array System

The Athena Phased Array system, manufactured by WesDyne NDE Products & Technology, consists of a pha
...
sed array acquisition system and PC running IntraSpect software. A PC is used to perform acquisition, analysis and storage of the data. System hardware is capable of operating up to four data sets with any combination of phased array or conventional UT probes. NOW AVAILABLE IN 64-64 CONFIGURATION.
>

Share...
We use technical and analytics cookies to ensure that we will give you the best experience of our website - More Info
Accept
top
this is debug window