Jominy End Quench Test
The Jominy End Quench Test ASTM A 255 measures Hardenability of steels. Hardenability is a measure of the capacity of a steel to be hardened in depth when quenched from its austenitizing temperature. Hardenability of a steel should not be confused with the hardness of a steel. The Hardness of a steel refers to its ability to resist deformation when a load is applied, whereas hardenability refers to its ability to be hardened to a particular depth under a particular set of conditions. Information gained from this test is necessary in selecting the proper combination of alloy steel and heat treatment to minimize thermal stresses and distortion when manufacturing components of various sizes.
Jominy End Quench Test Apparatus
Minimum Order Quantity: 1 Unit(s)
END QUENCH TEST APPARATUS
This apparatus is useful for determining the hardenability of steels by End Quench Test.
The test consists of heating a standard size specimen to a given temperature for a specific period of time, followed by a water quenching of one end under specified conditions and measuring the hardness at various points from quenched end along the length of test piece.
This apparatus conforms to IS : 3848 – 1981 and ASTM-A255.
After heating, the test specimen is kept on the specimen support, where it is automatically centered with respect to water jet. The quick action valve starts impinging the water jet on the specimen end instantly. The elaborate arrangement of pump, tank, pipe etc, enables to obtain desired correct water head for the nozzle. The electrical controls and safety devices for pump and motor are provided and the entire apparatus is totally enclosed.
Total length of test piece (mm)
100 ± 0.5
Dia of test piece (mm)
25 + 0.5
Inside dia of vertical water supply pipe (mm)
12.5 ± 0.5
Height of the free water jet (without test piece in position) (mm)
65 ± 10
Distance from Tip of nozzle to the bottom of test piece (mm)
12.5 ± 0.5
1 Ph, 230V, 50 Hz AC
Overall dimension (approx) (mm)
375 (L) x 285 (B) x 650 (H)
Net weight (approx) (Kg)
Jominy Test Fixture
Minimum Order Quantity: 1 Unit
JOMINI TEST FIXTURE
- The most commonly used method for determining hardenability is the end quench test developed by Jomini and Boegehold. The details of the test are covered in IS : 3848 – 1981 and ASTM A 255.
- In this test a normalized 25 mm diameter and 100 mm length test sample of steel to be evaluated is heated uniformly to its austenitizing temperature. The specimen is then removed from the furnace and placed in the end quench test Apparatus and immediately end quenched by a jet of room temp. water.
- After end quenching, longitudinal Flat Surfaces are ground on opposite sides of the test piece as per dimensions. This grinding is very important for correct positioning of the sample in the fixture and also for accurate repeatable and reliable test results.
- Jomini Test Fixture is to be positioned on the main screw of the hardness tester for checking hardness of the test sample. Hardness at equal intervals (1 mm or 1/16”) to be checked and noted.
- Plot the resulting data on graph paper with hardness value as ordinate (Y axis) and distance from the quenched end as abscissa (X axis). By comparing the curves resulting from end quench tests of different grades of steels, their relative hardenability can be established. Thus the flatter the curve, the greater the hardenability.