Test of resistance to intergranular corrosion of stainless steels (Streicher test)

Presentation for participants

Reference of the ILC: CO20SS1
References of test methods: ISO 3651-2 Met. C ASTM A262 Practice B ASTM G28 Practice A               
Frequency: Each year
Time schedule:  
Opening date of registrations Registration deadline Date of shipment of samples Start of the tests Deadline for carrying out the tests and providing the results Date of delivery of reports
15/11/2019 15/03/2020 20/05/2020 01/06/2020 15/07/2020 15/10/2020
Note: After the deadline, registrations are only accepted within the limit of availability of samples
Main characteristics: Pass/Fail (3 samples of 4 different types of stainless steels, showing various resistances to intergranular corrosion). Exposure time 20 h.
Other characteristics: Speed of corrosion (loss of mass in a fixed exposure time, 20h)
  Caution: The number of determinations may be low for the secundary characteristics, what may make inefficient the comparison between laboratories
Format of the test results: Results of some properties are numerical and some are of Yes/No type.
Determination of the assigned values (“true values” for each characteristic): By statistical computation of the totality of the results with possible selection on competence criteria (accreditation, validation by a reference body, quantity of tests performed in the year), test to detect possible collusion, merging of results not obtained in reproductibility conditions, suppression of technically unvalid results.
Type of statistical computation: For numerical results, the statistical computation will provide an assigned value with its attached uncertainty, values of standard deviations for repeatability and reproductibility, limits of alerts for bias and repeatability of the participant, indiviual values for uncertainty of results of participants.
  For results expressed as Yes/No type, samples are submitted to tests by sets of 2 items, with increasing severity, so that cut-off conditions for failure can be determined. The assessment of the results of participants is achieved by reference to this cut-off.
Number of products submitted to tests: 4 (4 different types of stainless steels)
Number of samples per participation: 3
Max number of operators per participation: 1 (it is necessary to order as many participations as there are participating test operators)
Product submitted to tests: Stainless steel
Type of samples: Bars
Approximate dimensions of samples: Ø8x75 mm
Specific preparation to be performed by the participant:  None (other than possible necessity to adapt dimensions of the test specimen to the equipment of the participant)
Special notice for this ILC: The determination of the speed of corrosion is not described in the reference standard, but it helps to make the proficiency test efficient.