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The principal interest in Horn Silver in these pages is as a cement for glass metals and minerals which gives a vacuum tight seal. A critical property of the material is the coefficient of linear expansion which is 31 x10-6 This compares with other significant materials as follows:
|MATERIAL||Coeff x 107|
|301 Stainless Steel||169|
The table demonstrates that the expansion coefficient of Horn Silver is much higher than various glasses and also higher than most metals. It might be expected that as a cement, horn silver would not be successful on this account. However, the reverse is the case, because Horn Silver is also quite soft as the Harness table shows.
|Material||Mohr Hardness||Y's modulus GPa|
|Brass||3 - 4||120|
|Steel||5 - 8||200|
The Young's modulus of Horn silver is also correspondingly low (only slightly larger than that of Douglas Fir (15)) This means that it is capable of absorbing dimensional changes, pressures or tensions which will arise with temperature changes when it is in contact with and enclosed by other materials. As long as the tenacity of the bond between it and neighbouring substances is strong, the natural elasticity of Horn Silver will sustain the integrity of the seal.