Providing Samples for Analytical Testing
To save time and money and to assure that the results are as accurate as possible, we ask customers to provide us with as much information as possible about samples submitted for analytical testing. The information will help us choose the most cost-effective testing methods and may eliminate the need to run preliminary tests that can delay results and increase costs.
Sample Composition
Since we perform analyses on a relatively large number of metal alloys, when a customer asks for the analysis of only one component of the alloy without giving us the approximate composition of the sample, errors may result. These errors can be related to interference of one of the elements with others in the alloy because of the analytical method used. Also, the errors may be related to incomplete separation of the elements during the dissolution of the sample that may be required to perform the testing.Standards & Specifications
Most of the testing at LTI is performed to determine if a sample conforms to a standard or specification, such as an ASTM (American Society of Testing and Materials), ASME (American Society of Mechanical Engineers) or a MIL (Military). It is important to know the alloy or grade that is being tested because some standards refer to more than one alloy or grade.Sample Size
To assure that we have an adequate sample size to perform the required analytical chemistry tests, we provide the following guidelines:- The sample should be 1/8” thick and 1” x 1” square for Optical Emission Spectroscopy (OES) of solid samples.
- When OES analysis for gases is required, the sample size is weight dependent. For carbon and sulfur the sample should weigh a minimum of 2 grams, for nitrogen and oxygen the sample should weigh a minimum of 1½ grams and for hydrogen the sample should weigh a minimum of 2 grams.
- Samples that require testing by Inductively Coupled Plasma (ICP) or Atomic Absorption (AA) should weigh a minimum of 5 grams.