A combustion calorimeter (1) has a housing (6) and therein a detachably mounted decomposition vessel (2) with sample holder (11) and ignition apparatus (12) in its reaction chamber (3). The wall (4) of the decomposition vessel (2) and also the upper decomposition wall (5) here have in the vertical use position a wall thickness that increases from the bottom to the top in order to conduct the heat generated in a combustion process if possible into the upper region of the decomposition vessel (2), where also at least one temperature sensor (7) can be arranged. Owing to the increase in thickness of the delimitation of the internal or reaction space (3), the heat can be distributed therein more favorably.

An apparatus for testing a sample includes a fixture releasably holding the sample during a test, a first mixer having a first chamber and a first channel, the first chamber mixing compressed air with abrasive particles to form a first mixture having a first predetermined mixing ratio, the first channel projecting the first mixture at a spot of the sample during the test, a second mixer having a second chamber, an ignitor and a second channel, the second chamber mixing an oxidizer and a fuel to form a combustible mixture with a second predetermined mixing ratio, the ignitor adjacent to an outlet of or protruding into the second chamber and controllably igniting the combustible mixture to create a flame, the second channel projecting the flame at the spot during the test, and a first temperature sensor measuring a surface temperature of an unexposed side of the sample during the test.

An apparatus for testing a sample includes a fixture releasably holding the sample during a test, a first mixer having a first chamber and a first channel, the first chamber mixing compressed air with abrasive particles to form a first mixture having a first predetermined mixing ratio, the first channel projecting the first mixture at a spot of the sample during the test, a second mixer having a second chamber, an ignitor and a second channel, the second chamber mixing an oxidizer and a fuel to form a combustible mixture with a second predetermined mixing ratio, the ignitor adjacent to an outlet of or protruding into the second chamber and controllably igniting the combustible mixture to create a flame, the second channel projecting the flame at the spot during the test, and a first temperature sensor measuring a surface temperature of an unexposed side of the sample during the test.