Re: Rockwell Vs. UTS

Posted by Gordon England on May 09, 2003 at 02:54:37:

In Reply to: Rockwell Vs. UTS posted by Michael Doyle on May 08, 2003 at 19:36:06:

: I have a dispute regarding Rockwell and ultimate tensile strength. Someone is telling me that there is a direct correlation between UTS and the rockwell test. I don't believe that they are interchangeable. I can't understand how the pull test employed by UTS testing directly corelates to a materials resistance to a compressive depression. I don't believe that different materials with the same rockwell will have the same UTS. Can anyone offer some insight?

Hi Michael

Great query, in part I would agree with your dispute.

First I would like to stress that typical hardness scale conversion tables and conversions to ultimate tensile stress are at best approximate. The tables are built up through comparison and not a magical formula.

Hardness measurement particularly in the steel industry is commonly used as a guide to UTS values as the test is quick and relatively easy.
With a specific material and enough comparative tests, quite accurate correlations can be made. But, it must be remembered that while hardness and strength have a close relationship, the tests and properties measured are very different and you cannot expect to have a universal correlation, particularly when considering different test materials.

Regards Gordon

Follow Ups:

Surface Engineering Forum

Surface Engineering Message Board Archive

Surface Engineering Message Board Archive Index

Post A Message!

Gordon England Surface Engineering ForumPlease go to the new Surface Engineering Forum as this old message board is a read only archive. Please copy and paste relevant information or link to the page if you wish to reactivate a thread on the new forum.

Gordon England Independent Thermal Spray Coating Consultant
Telephone: +44 (0)1252 405186


Site Links


Nature of Thermal Spray Coatings

Surface Engineering in a Nutshell

Surface Engineering Forum

Thermal Spray Gun Repair Service

Plasma Consumable Parts

Thermal Spray Powder Supplies


Thermal Spray Coatings on Carbon and Glass Fibre Reinforced Polymers

HVOF Coating of Paper Making Roll

Abradable Coatings


Thermal Spray Processes:

Combustion Wire Thermal Spray Process

Combustion Powder Thermal Spray Process

Arc Wire Thermal Spray Process

Plasma Thermal Spray Process

HVOF Thermal Spray Process

HVAF Thermal Spray Process

Detonation Thermal Spray Process

Plasma Flame Theory

Cold Spray Coating Process

Wear and Use of Thermal Spray Coatings

Corrosion and Use of Thermal Spray Coatings

Glossary of Thermal Spray and Surface Engineering Terms

Image Directory for Thermal Spray Coatings

Plasma Gas Flow Information

Plasma Gas Flow Correction Calculator

Contact Form

Links to other interesting sites related to thermal spray and surface engineering

Reciprocal Links

Periodic Table of the Elements

SI Units

Calculators for Conversion between Units of Measurement

Hardness Testing

Surface Engineering Message Board Archive

Surface Engineering Message Board Archive Index

Photography Gallery2

Photography Gallery3

© Copyright Gordon England