Synthetic magnesium silicate Synthetic magnesium silicate Synthetic magnesium silicates are white, odorless, finely divided powders formed by the precipitation reaction of water-soluble sodium silicate (water glass) and a water-soluble magnesium salt such as magnesium chloride, magnesium nitrate or magnesium sulfate. The composition of the precipitate depends on the ratio of the components in the reaction medium, the addition of the correcting substances, and the way in which they are precipitated. The molecular formula is typically written as MgO:XSiO, where X denotes the average mole ratio of SiO to MgO. The product is hydrated and the formula is sometimes written MgO:XSiO•HO to show the
Magnesium alloy the elongation of the alloys but results in decreased strength. Magnesium alloys harden rapidly with any type of cold work, and therefore cannot be extensively cold formed without repeated annealing. Sharp bending, spinning, or drawing must be done at about , although gentle bending around large radii can be done cold. Slow forming gives better results than rapid shaping. Press forging is preferred to hammer forging, because the press allows greater time for metal flow. The plastic forging range is . Metal worked outside this range is easily broken. Magnesium alloys, especially precipitation hardened alloys, are used in casting. Sand,