Which of the following will increase the strength of a sample of 90% SiO2 - 10% MgO
Quench the entire sample in water Quench half of the sample in water Cool the entire sample with air jets Cool half the sample with air Submerge the sample in a salt bath of Na2O Submerge the sample in a salt bath of CaO
To determine which option will increase the strength of a sample of 90% SiO2 - 10% MgO, we need to consider the properties of the substances involved.
Quenching refers to a rapid cooling process that may or may not affect the strength of the sample. Cooling with air jets is a slower cooling process compared to quenching in water.
Exposing the sample to a salt bath of Na2O or CaO involves submerging the sample in a molten salt solution. Both Na2O and CaO are oxides of alkali and alkaline earth metals, respectively. They may react with SiO2 and MgO, potentially leading to changes in the strength of the sample.
Based on these considerations, the option that is most likely to increase the strength of the sample is submerging the sample in a salt bath of Na2O. The reactivity between Na2O and SiO2 - MgO may create interparticle bonds, enhancing the strength of the sample.
It's important to note that the actual effect on strength can vary based on the specific conditions, composition, and other factors. Experimental testing or consulting with materials experts would provide more accurate information on the effects of these treatments on the strength of the sample.