Mechanical properties of magnesium oxysulphate cements

Having prepared the cements, a number of physical techniques were employed to study them. Porosity was determined by measuring the apparent volume and the solid volume, the former by straightforward linear measurement, the latter using a helium pycnometer. This technique was used to avoid the problems of dissolution that arise when water is used 

In addition to porosity, modulus of elasticity and microhardness were determined. Differential thermograms were recorded, at a heating rate of 20 ° min-.  

One important finding which did emerge from the work of Beaudoin Ramachandran (1978) was that, contrary to previous assumptions. 

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