Friday, 17 July 2015

Testing of Automotive Coating

American Society for Testing Materials (ASTM)

Over 12,000 ASTM standards operate globally. Defined and set by us, they improve the lives of millions every day. Combined with our innovative business services, ASTM standards enhance performance and help everyone have confidence in the things they buy and use – from the toy in a child’s hand to the aircraft overhead.

Working across borders, disciplines and industries we harness the expertise of over 30,000 members to create consensus and improve performance in manufacturing and materials, products and processes, systems and services.

Understanding commercial needs and consumer priorities, we touch every part of everyday life: helping our world work better. ASTM's paint and related coating standards are instrumental in specifying and evaluating the physical and chemical properties of various paints and coatings that are applied to certain bulk materials to improve their surface properties.

Guides are also provided for the proper methods of applying these coatings, which also include enamels, varnishes, electroplating, pigments, and solvents. These paint and related coating standards help paint manufacturers and end-users in the appropriate testing and application procedures for the coating of their concern.

List of paint standards and related coating standards developed by ASTM -…/paint-and-related-coating-standards.h…

Standard conditions for temperature and pressure

A standard sets of conditions for experimental measurements established to allow comparisons to be made between different sets of data. The most used standards are those of the International Union of Pure and Applied Chemistry (IUPAC) and the National Institute of Standards and Technology (NIST), although these are not universally accepted standards. Other organizations have established a variety of alternative definitions for their standard reference conditions.

In chemistry, IUPAC established standard temperature and pressure (informally abbreviated as STP) as a temperature of 273.15 K (0 °C, 32 °F) and an absolute pressure of exactly 100,000 Pa (1 bar, 14.5 psi, 0.9869 Atmospheric pressure). An unofficial, but commonly used standard is standard ambient temperature and pressure (SATP) as a temperature of 298.15 K (25 °C, 77 °F).

NIST uses a temperature of 20 °C (293.15 K, 68 °F) and an absolute pressure of 101.325 kPa (14.696 psi, 1 atmosphere). The International Standard Metric Conditions for natural gas and similar fluids are 288.15 K (15.00 °C; 59.00 °F) and 101.325 kPa.

Based upon the American Society for Testing Materials (ASTM) - Testing of Automotive Coating
Scratch Resistance

The scratch resistance was determined in accordance with AS 1580 Method 403.1
A tungsten carbide needle is slid over the surface. The load required for the needle to penetrate through to the substrate is used to indicate the scratch resistance.

· Chemical Resistance
The chemical resistance of the coating was determined in accordance with ASTM D1308-02
Concentrated Hydrochloric acid, Phosphoric acid, and Ethanol were applied to the surface of the coating, covered and allowed to be in contact with the surface for one hour. The surface was then washed with distilled water, allowed to dry and then inspected.

· Resistance to ultra violet radiation
UV resistance was determined in accordance with ASTM G155
Using Xenon Arc Light allows reproduction of the weathering effects occurring when materials are exposed to sunlight (either direct or through window glass) and moisture. Test for colour fastness and accelerated life testing to long term UV exposure. Find out if the coating will withstand years’ worth of UV weathering.

· Pencil Hardness (no AMST)
Make a line about 1/2-inch long. If the pencil you start with scratches the surface of the coating, then go down the pencil grades until you come to the first pencil that doesn't scratch the coating. Redo the test, and if you get the same results, you have determined the 'Pencil Hardness' of the coating you are testing.

Other Test available

  •          Standard Practice for Testing Water Resistance of Coatings Using Water Immersion - ASTM D870
  •          Standard Practice for Conducting Exterior Exposure Tests of Paints and Coatings on Metal Substrate - ASTM D1014
  •          Standard Practice for Fluorescent UV-Condensation Exposures of Paint and Related Coatings - D4587 - 11


Certification Testing is one step above Compliance Testing. Certification has a legal connotation signifying that a third party organization has put its stamp of approval on the outcome and has, in a sense, guaranteed that the products meet the conditions of the test.

Testing and Product Certification Program should be carried out in accordance with ISO / IEC 17065 by a member of the American Association for Laboratory Accreditation (A2LA)

An example Test / Certification Report
TÜV Rhineland -…/T%C3%9CV-Testrapport-Opti-Coat-Pro…

Always be willing to learn; because the more you learn, the more you’ll realize what you don’t know. It is said that knowledge is power, with the caveat that it includes access to a reliable information sources. I would like to think that these articles become an asset to anyone who is new to detailing and to professional’s alike, as well as industry experts who seek to advance their knowledge.
I hope these articles are informative. They are based on the current status of technical development as well as my experience with the products.

By having some understanding of the ‘What’ and ‘Why’ as well as the ‘How’ along with a little science to help you understand how the chemicals we use react, you can achieve the results you desire.

I would appreciate it if you would share these articles as it helps other detailers further their knowledge.

As always if you have questions, I’ll do my best to answer; bear in mind the only stupid questions is the one that was unasked. Questions and/ or constructive comments are always appreciated

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