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What is the cubical coefficient of thermal expansion for metals?
Wiki User
∙ 13y ago
Since most metals are isotropic, the cubical coefficient of expansion is three times the linear coefficient of expansion.
The linear coefficient of expansion is obtained from measurement and tables for the specific material which are readily available.
Wiki User
∙ 13y ago
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How do you calculate compression of metals if they cooled under -73 degree temperature?
Either the question is misworded, or more information is needed. Compression implies load; in order for a peice of metal to be loaded by a temperature change, it would need to be rigidly restrained by something with a different coefficient of thermal expansion. If you mean what is the dimensional change, that is answerable. It is as follows: (original size) X (coefficient of thermal expansion) X (temperature difference) = (change in length) You need to look up the coefficient of thermal expansion, and make sure you get the units right: /°C or /°F
Which material can be used as bimetallic strip?
You may use any two metals which have different thermal expansion properties. Steel and brass are commonly used because of cheapness. There is not even a need for them to be metals - you could bond two glasses of different thermal properties, and these would bend as well.
What are the characteristics of ceramics?
Physical properties means the behavior of materials in response to physical forces other than mechanical, such as; Volumetric, thermal, electric and electrochemical properties. Most Ceramics are lighter than metals but heavier than polymers. Most ceramics have a higher melting point than most metals as it is that some ceramics such as China can with stand high temperatures to about 1200 degrees centigrade. Ceramics also has lower Electrical and Thermal Conductivity than most metals but the range of value is greater in ceramics permitting some ceramics to be used as insulators, for example Porcelain insulators and others as conductors like Lithium-ion conducting glass-ceramics and oxide ceramics. Thermal expansion is another physical property of ceramics, Ceramic thermal expansion coefficients are less than those of metals but effects are more damaging in ceramics bringing about cracks and other failures(Thermal shock and thermal cracking) as for ceramic materials with relatively high thermal expansion and low thermal conductivity however there is glass ceramics that has low thermal expansion thus resisting thermal shock and thermal cracking, for example Pyrex glass ceramics. Thus the physical properties being but not limited to permeability, elasticity, considerable strength, hardness, brittleness, resistance to chemical attack and thermal shock.
What is the thermal expansion coefficient for iron oxide?
The CTE of Silica depends on it's state. Crystalline Silica has a much higher Coefficient of Thermal Expansion than fused - or glassy silica. Crystalline Silica CTE is dependent on the axis along which a single crystal in mounted. Along the z-axis CTE is as high as 12 x 10^-6 / degree C. Perpendicular to the z-axis CTE is 20 x 10^-6 / degree C (range ambient to 550C). Amorphous Silica CTE is listed as 0.55 x 10^-6 /degree C
What is the difference between positive and negative temperature coefficient of resistance?
Negative temperature coefficient of resistance means that as the temperature of a piece of wire or a strip of semiconducting material increases, the electrical resistance of that material decreases.
Why should the coefficient of thermal expansion of a refractory metal be the lowest?
refractory metals have high melting points and are used in extremely hot environments; if expansion coefficient is lower this prevents high stresses that can develop due to thermal gradients during the high heat up. It helps to have high thermal conductivity as well
Why measuring scale should be made up of insulators or metals whose coefficient of linear expansion is small?
Using insulators or metals with a small coefficient of linear expansion ensures that the scale does not expand or contract significantly with changes in temperature. This helps maintain the accuracy of the measurements taken using the scale, as it minimizes any distortions due to thermal expansion. Additionally, insulators or materials with low thermal expansion are more stable and less prone to warping, which further ensures the reliability of the scale.
What happens to bimetallic strip when it is heated and cooled?
When a bimetallic strip is heated, the two metals expand at different rates causing the strip to bend towards the metal with the lower coefficient of thermal expansion. Conversely, when the strip is cooled, it bends towards the metal with the higher coefficient of thermal expansion. This bending action can be harnessed for applications like thermostats and temperature-sensitive switches.
Would a bimetallic strip work if the two different metals happened to have the same rates of expansion?
No, a bimetallic strip relies on the different rates of expansion of the two metals to produce a bending effect when exposed to temperature changes. If the two metals have the same rates of expansion, the strip would not bend and would not function as intended.
How do you calculate compression of metals if they cooled under -73 degree temperature?
Either the question is misworded, or more information is needed. Compression implies load; in order for a peice of metal to be loaded by a temperature change, it would need to be rigidly restrained by something with a different coefficient of thermal expansion. If you mean what is the dimensional change, that is answerable. It is as follows: (original size) X (coefficient of thermal expansion) X (temperature difference) = (change in length) You need to look up the coefficient of thermal expansion, and make sure you get the units right: /°C or /°F
When a bimetallic strip is heated it bends toward the metal with the thermal expansion?
When a bimetallic strip is heated, the metal with the higher coefficient of thermal expansion expands more than the other metal, causing the strip to bend towards that metal. This bending is due to the unequal expansion and contraction of the two metals when exposed to different temperatures.
Does titanium expand a lot when heated compared to other metals?
Titanium has a relatively low thermal expansion coefficient compared to other metals, meaning it expands less when heated. This property makes it useful in applications where dimensional stability is important.
Which structure would expand or contract in response to changes in the outside temperature?
A material with a high coefficient of thermal expansion, such as metals or concrete, would expand or contract in response to changes in outside temperature. Another example is bimetallic strips, which consist of two different metals bonded together and used in thermostats or thermal switches.
What is the thermal conductivity coefficient of porcelain?
The thermal conductivity coefficient of porcelain is typically around 1-2 W/mK. This means that porcelain is a relatively poor conductor of heat compared to metals, which have much higher thermal conductivity values.
What solids expand when heated?
Most solids expand when heated due to increased thermal energy causing the atoms or molecules within the solid to vibrate more and increase their separation distance from each other. This expansion is governed by the material's coefficient of thermal expansion, which varies depending on the specific solid. Examples include metals, glass, and concrete.
What is a bimetallic strip and What is it used for?
A bimetallic strip is a strip made of two different metals that have different coefficients of thermal expansion. When heated or cooled, the strip bends due to the difference in expansion rates between the two metals. This principle is used in devices such as thermostats to regulate temperature.
How can expanding metal be measured?
Metal expansion can be measured using a variety of instruments like thermometers, thermocouples, or strain gauges. By subjecting the metal to different temperatures and observing the resultant expansion, the coefficient of thermal expansion can be calculated. Additionally, techniques such as interferometry or laser holography can be used to measure the expansion of metals with high precision.
