Hardness Tester

[Way-Barney]

Dropped on a new hardness tester today. Never heard of them. Looks ok though, full manuals etc.

 

[DeadboxHero]

Dropped on a new hardness tester today. Never heard of them. Looks ok though, full manuals etc.
View attachment 2481878

That is the control panel on a older vickers hardness tester. It will require more surface preparation and flatness, it will also be slower and can be more prone to error in measurement than HRC.

if the material being measured has a lot of non-uniformity it will also have more variation in results even if done perfectly.


It puts a small, pyramid-shaped indentation into a material and then you measure the area of the indentation.

That's why your surface preparation is going to be very, very important.

It should have a microscope integrated with the tester.

Make sure to follow the test standards carefully before reporting hardness values to others.

 

[Way-Barney]

That is the control panel on a older vickers hardness tester. It will require more surface preparation and flatness, it will also be slower and can be more prone to error in measurement than HRC.

if the material being measured has a lot of non-uniformity it will also have more variation in results even if done perfectly.


It puts a small, pyramid-shaped indentation into a material and then you measure the area of the indentation.

That's why your surface preparation is going to be very, very important.

It should have a microscope integrated with the tester.

Make sure to follow the test standards carefully before reporting hardness values to others.

Thanks for that.

Did you find it OK?

 

[DeadboxHero]

Thanks for that.

Did you find it OK?

Ok for what? It's a more specialized hardness test.

For knives you'll have to convert Hv to HRC. Most knife people do not communicate hardness in the community with Hv. Also, there can be some accuracy lost with conversion to HRC. So, It's not recommended to use conversions, especially if there's some form of discrepancy between one person's hardness values and another person's values.

The benefits of Vickers hardness testing would be more for research.


For example, using Hv for trying to isolate the specific hardnesses of individual phases or deeper analysis of hardness changes with certain types of processing or failure analysis.

It is not a replacement for HRC. Most materials labs will have both because they do different things.


As a knife maker, understand your time is the most valuable resource you have, so if you have to add extra processing and abrasives to prep for testing just to get a simple hardness value that's going to also take longer to measure It's kind of a bum deal.

There's simply no return on the time investment compared to slamming a 120 grit finish on a sample and blasting a quick HRC test average for rapid QC.

It's going to cost you more in the end for using it in that role compared to just using a Rockwell hardness tester.

If it's all you have, it's better than nothing, but you're going to have to do your best to research (Bladeforms is not enough) more Vickers focused sources so you can to make it function accurately.

Have you looked at the testing standards for Vickers? That's a good start.

Posting questions here about how to use Vickers hardness will not be fruitful. It's not a tool knife makers regularly use or need. So you're going to have to put your own work in.

I'm not trying to make anyone upset, It's just it is simply not as forgiving of a tool especially for some people that like to "wing it" and share goofy hardness values.

Best wishes on your journey.

Cheers

 

[Ken H>]

That is the control panel on a older vickers hardness tester. It will require more surface preparation and flatness, it will also be slower and can be more prone to error in measurement than HRC.

if the material being measured has a lot of non-uniformity it will also have more variation in results even if done perfectly.


It puts a small, pyramid-shaped indentation into a material and then you measure the area of the indentation.

That's why your surface preparation is going to be very, very important.

It should have a microscope integrated with the tester.

Make sure to follow the test standards carefully before reporting hardness values to others.

That is interesting - thanks for posting it. That's the way I use my HR150 to test hardness of lead for bullet casting. I've got a 1/2" ball applied with 150kg force. Measure the diameter of indention under microscope and calculate the BNH using a spreadsheet.

 

[Way-Barney]

I have had a play around with this today, more in familiarization that a testing regimen.

Calibration plate was 60.3 HRC




I then tested a hardened piece of O-1 that was expected to be 60-61 HRC, no prep as such, straight out the oven with a quick rub of 1000 grit to brighten up the image in the viewfinder more than anything.



Of course everything raced through my mind when results were not as expected, oven, quench, temper etc
Then I realized that this is so accurate that I was measuring, in all probability, the decarburized layer of the steel.
I came up with a good idea though, I will micro the steel thickness tomorrow and polish-recheck. Then a couple more times to try and establish the thickness of the decarb my method produces.
Or it just could start the investigation of other process errors.
Overall I am pleased.