Hardness testing

Ted Stroud
QA / QC United Kingdom, Joined Jul ,
2
Ted Stroud
QA / QC
United Kingdom,
Joined Jul
2

QA / QCUnited Kingdom,Joined Jul

AJR contains other products and information you need, so please check it out.

09:37 Jul-20-

https://www.ndt.net/forum/thread.php?msgID=#

Hardness testing 09:37 Jul-20-

I am currently introducing in-house raw material hardness testing. I am using a Foundrax Model 134 Portable Brinell Hardness Tester to undertake the work. I have about a 600mm x 120mm throat size. My average raw bar Ø are around 8”-10” and approximately 12”- 20” long.
My procedure calls for 4 test points on each end of the material.

As i am pretty new to this field, my question is has anyone got any good solutions to the best way of setting up to undertake the physical testing. Currently i set the hardness tester on its side using V blocks and role the material into the throat, working at floor level.

Really I am looking for some inspiration to make the process as safe and efficient as possible. Any suggestions gratefully received.

Nigel Armstrong
Engineering, - Specialist services United Kingdom, Joined Oct ,

Nigel Armstrong
Engineering, - Specialist services
United Kingdom,
Joined Oct

Engineering, - Specialist servicesUnited Kingdom,Joined Oct

20:52 Jul-21-

https://www.ndt.net/forum/thread.php?msgID=#

Re: Hardness testing 20:52 Jul-21-In Reply to Ted Stroud at 09:37 Jul-20- (Opening).

Ted

I have never handled the Foundrax 134 but having checked their website I can see why you are struggling.

You say you are new to the field so are you aware of machines such as the MicroDur, MIC 10 or Equotip? These machines are ideal for your application of solid bars. They work on rebound dynamics and the probe is connected to the electronics by a cable so its eaasily manipulated and can convert electronically to many different hardness tables . Have a look at GE Instruments for their catalogue or Google Equotip.

Sorry I cant help with manipulation of the Foundrax.

Vicky
NDT Inspector, Blue Star Limited IE , India, Joined May ,
29
Vicky
NDT Inspector, Blue Star Limited
IE ,
India,
Joined May
29

NDT Inspector, Blue Star LimitedIE ,India,Joined May

11:02 Jul-25-

https://www.ndt.net/forum/thread.php?msgID=#

Re: Hardness testing 11:02 Jul-25-In Reply to Nigel Armstrong at 20:52 Jul-21- .

Hi Ted,
I fully aggree with the post of Mr Nigel as far as your job & your procedure discription is concerned making use of Equitip or any rebound type hardness tester are very effective, since you are also intrested in taking only point measurements its the best suit for you.


regards

Vignesh M

Michael Lewis
NDT Inspector, Quality Manager Tejas Testing & Inspection, USA, Joined Mar ,
10
Michael Lewis
NDT Inspector, Quality Manager
Tejas Testing & Inspection,
USA,
Joined Mar
10

NDT Inspector, Quality ManagerTejas Testing & Inspection,USA,Joined Mar

18:46 Jul-26-

https://www.ndt.net/forum/thread.php?msgID=#

Re: Hardness testing 18:46 Jul-26-In Reply to Ted Stroud at 09:37 Jul-20- (Opening).

Be aware that most end users do not accept Equotip or similar rebound testers as a valid hardness test. They allow you to use it for sorting purposes, but not for final inspection. So before you go blowing a few thousand dollars on some equotip machine, keep in mind that half the procedures out there specifically ban it and your customers may be asking for it to get retested in many cases.

Also, I have never heard of setting the hardness tester "on it's side." I would check with manufacturer to make sure it is an allowable practice. The standards I work with do not address this configuration and it would be worth checking to see if your load can be applied properly when horizontal.

Another idea that I have played around with but haven't put into practice (I don't do HBW often enough) uses pipe racks and a chair. In a warehouse setting (smooth, level flooring), you could put the material on pipe racks. Get an office chair (or similar apparatus to your imagination) and put the hardness tester on the seat of it. Maybe get rid of the seat entirely and use a flat piece of plywood. Anyhow, the idea is to use the feature of many office chairs that allows it to raise up and down. Then you can secure the tester to the chair and adjust the height to match the bars. Final step would be to wheel the tester around to the bar (instead of rolling the bar) and you would save your back and some sweat.

Someone let me know if that idea is ridiculous so I know to whether to try it myself or not.

Nigel Armstrong
Engineering, - Specialist services United Kingdom, Joined Oct ,

Nigel Armstrong
Engineering, - Specialist services
United Kingdom,
Joined Oct

Engineering, - Specialist servicesUnited Kingdom,Joined Oct

01:45 Jul-27-

https://www.ndt.net/forum/thread.php?msgID=#

Re: Hardness testing 01:45 Jul-27-In Reply to Michael Lewis at 18:46 Jul-26- .

Ted

You are in the UK so this may not apply - it depends on the contractual soecification, if any. ASTM specification A-956 Equotip Hardness Testing of Metallic Materials has been around for 10 years. You say you are introducing hardness testing so it seems you arre calling the shots. As such im certain if you demonstrate compliance with A-956 it would be a very bloody-minded end user who would not sanction its use

Your application of heavy steel bars is ideally suited for its use. By rolling the bar so you are always testing at 12 o'clock you will optimise test accuracy. I would prefer you to use Equotip in the proper way than the Foundrax in a manner it was not designed for.

Hope this helps

Ted Stroud
QA / QC United Kingdom, Joined Jul ,
2
Ted Stroud
QA / QC
United Kingdom,
Joined Jul
2

QA / QCUnited Kingdom,Joined Jul

08:53 Jul-27-

https://www.ndt.net/forum/thread.php?msgID=#

Re: Hardness testing 08:53 Jul-27-In Reply to Ted Stroud at 09:37 Jul-20- (Opening).

I would like to thank you guys for giving me food for thought. I have already got an EQUOTIP in my inspection department. As stated some specs prohibit the use of the equipment, but I am interested in doing comparisons in the results achieved.

Nigel Armstrong
Engineering, - Specialist services United Kingdom, Joined Oct ,

Nigel Armstrong
Engineering, - Specialist services
United Kingdom,
Joined Oct

Engineering, - Specialist servicesUnited Kingdom,Joined Oct

Want more information on Ultrasonic Hardness Tester? Feel free to contact us.

09:51 Jul-27-

https://www.ndt.net/forum/thread.php?msgID=#

Re: Hardness testing 09:51 Jul-27-In Reply to Ted Stroud at 08:53 Jul-27- .

Good morning Ted

The 06 editon of A-956 has been renamed (maybe to move away from the proprietary Equotip name in its title) to Standard test Method for Leeb Hardnes testing. I dont have the newer version, but I believe it still relates to the Equotip Method.

For the MIC 10/20 and other UCI instruments, ASTM A- Standard Practice for Portable Hardness Testing by the Ultasonic Contact Impedance Method

I should have perhaps been a bit more circumspect in my OP as Michael pointed out as oth methods do only measure surface hardness and not bulk hardness that will be measured by an indentor. So it usage would depend on the material condition. However the referenced ASTMs standardise the methods to give them much more credibility when used properly.

If you are tied by specifications to use of an indentor method then the above are of no use unless their use ic conceded. But as Michael points out use of an indentor lying on its side is hardly kosher! I hope you fiind a convenient solution to your predicament.

S.V.Swamy
Engineering, - Material Testing Inspection & Quality Control Retired from Nuclear Fuel Complex , India, Joined Feb ,
787 3
S.V.Swamy
Engineering, - Material Testing Inspection & Quality Control
Retired from Nuclear Fuel Complex ,
India,
Joined Feb
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Engineering, - Material Testing Inspection & Quality ControlRetired from Nuclear Fuel Complex ,India,Joined Feb

16:04 Jul-27-

https://www.ndt.net/forum/thread.php?msgID=#

Re: Hardness testing 16:04 Jul-27-In Reply to Nigel Armstrong at 09:51 Jul-27- .

Dear Friends,

I was following the discussion with a lot of interest. In my own long career, I had the good opportunity to perform hardness testing of zircaloy and steel bars / billets etc. on the shop floor (yes, I did the initial testing with my own hands and then trained the technicians to use it). We had all the different methods that are being discussed. Indentation, rebound, spring / hydraulic driven / ultrasonic...

C type indentation hardness testers that depend on screw / hydraulic pressure can be used in horizontal position. I checked the Foundrax website and they clearly mention that the model 134 can be used in any position, implying that it is not gravity driven!

Since they use the standard indenters and apply the full load, they meet the hardness testing specifications / standards fully.

Superficial / surface indentation testers and rebound testers, ultrasonic testers etc. give the surface hardness, which may or may not represent the internal hardness of the material. Only machined bars and billets probably satisfy the condition where the surface hardness is close to the internal hardness. If the bars are having scale, we may need to grind a few spots and check those spots.

Regards.

S.V.Swamy
Quality Consultant

Simon Amallraja
Simon Amallraja
17:55 Jul-27-

https://www.ndt.net/forum/thread.php?msgID=#

Re: Hardness testing 17:55 Jul-27-In Reply to Ted Stroud at 09:37 Jul-20- (Opening).

You can also try Ultrasonic mode of Case Hardening, using UT Equipment with related Software meant for Hardness Measurement.

There are many manufacturers and you can check for Autoscan or . You need to check the details and decide as per your reqt

Simon

 

The Ultrasonic Contact Impedance (UCI) hardness test method was developed by Dr. Kleesattel in .

UCI testers are portable electronic devices that use a spring to apply a known force to a Vickers diamond indenter which is attached to the end of a resonating rod. As the resonating rod and Vickers diamond pyramid indenter penetrate the test sample the resultant indentation creates a clamping force to the tip of the indenter that is proportional to its size and causes a frequency shift to the rod. The amount of the frequency shift is measured and related to the size of the Vickers indentation. Results are converted to hardness scales such as Vickers and Rockwell and Brinell.

Test samples must be smooth in relation to the indentation size and scale with other interfering coatings removed..

When testing materials other than steel, calibration to &#;secondary&#; standards made from the specific type of material to be tested is advised.

Advantages of the UCI test method

• Measures only surface hardness
• Highly portable
• Test in any direction
• Can measure the hardness of a coating, plating or case hardened surface
• Small indentation is virtually nondestructive
• Small probe can access the heat affected zones of welds, gear teeth and splines.
• UCI testers can be used to measure the hardness of pipe, tanks, etc., with a thickness greater than 1/16&#; &#; 1/8&#; (1.5 mm - 3mm), (depending on probe-load and material hardness). Compare to &#;Dynamic/Rebound&#; type testers that require a minimum of .4&#; (10mm)* due to &#;spring or drum&#; effect. 
• Complies with ASTM A-05 & DIN Standard Practice for Portable Hardness Testing by the Ultrasonic Contact Impedance Method
• A copy of the standard is available on https://www.astm.org/Standards/A.htm

Probe choice:

Choose a probe (load) relative to the thickness of the part/coating and surface roughness.

• 10 kg Probe of inspection of steel pipe, pressure vessels, etc. Typical conversion to HB.
• 5 kg. Probe for hardened gears, splines, shafts, etc. Typical conversion to HRC.
• 0.3, 1,2 kg Probes for thin and coated materials. Typical conversion to Vickers or HRC.

Common brands that exist are:-

Novotest TU2

GE Mic 10/20

Equotip 550 UCI

Some things to keep in mind - Sufficient mass and thickness are required to prevent the part from going into self-oscillation. Requirements for the UCI method are not as demanding as the rebound method. In fact, the size of most standard test blocks is adequate for testing.

Due to the relatively shallow indentations created, special attention must be given to the surface condition and preparation of the part. The indentation must be large in comparison to the surface roughness. If surface preparation is required, care must be taken not to alter the surface hardness by overheating.

Alignment of the probe with respect to the surface is important to create a proper indentation for measurement. Fixtures aid in alignment and should be used whenever possible. When testing conditions require handheld measurement, operator technique will influence the results and additional variation in the results should be expected.

The UCI method is best suited for materials having a homogeneous microstructure. The small size of the sampled area is unable to provide consistent and dependable results on most cast and forged materials. 

For more information, please visit Ultrasonic Hardness Tester for Sale.