The standard specifies exactly what information must be included in a test report, such as a description of the specimen, the testing conditions (speed, temperature, humidity), the number of specimens tested, and the calculated results.
: A "free PDF" is always an unofficial copy. You are taking a risk regarding the authenticity and completeness of the document. Most critically, it will not be the current standard and should never be used for official compliance or product certification.
: Uses "dumbbell" (dogbone) or ring-shaped test pieces. Common dumbbell types are numbered 1 through 6. jis k 6251 pdf free
In some scenarios, continuous ring specimens are utilized. Ring specimens eliminate the risk of "grip slippage" because they are looped around rotating spindles on the test machine, though they create non-uniform stress concentrations along the inner radius. Summary of the Test Procedure
The testing machine must feature a power-driven grip mechanism capable of moving at a constant rate of separation. For most JIS K 6251 evaluations, the standard crosshead speed is set to , though certain specialized compounds may dictate alternative speeds. 2. Extensometers vs. Crosshead Travel The standard specifies exactly what information must be
: Applicable specifically to rubbers with a defined yield point. Accessing JIS K 6251 PDF Files
Instead of chasing risky free downloads, use the offered by JSA, check your university or corporate library , or purchase a single copy for less than the cost of two hours of lab time. For most rubber testing needs, the official JIS K 6251 PDF is a modest investment that ensures your results are accepted anywhere in the world — especially in the demanding Japanese market. Most critically, it will not be the current
: Applied specifically to materials that exhibit a distinct yield point.
Industry bodies like the or Society of Rubber Science and Technology (Japan) sometimes offer member access to bundled standards at a low fee.
If you are a student or work for a large manufacturing company, your university library or corporate R&D department may have a subscription to a standards database (like IHS Markit, Techstreet, or directly from JSA) that provides free access to the standard for internal use.
: Often referred to as "modulus" (e.g., 100% or 300% modulus). Yield Points