In the field of precision measurement, granite precision platform with its excellent stability, high hardness and good wear resistance, has become the ideal foundation support for many high-precision measurement work. However, the temperature fluctuations in the environmental factors, like the "precision killer" hidden in the dark, have a non-negligible impact on the measurement accuracy of the granite precision platform. It is of great significance to investigate the influence threshold deeply for ensuring the accuracy and reliability of measurement work.
Although granite is known for its stability, it is not immune to temperature changes. Its main components are quartz, feldspar and other minerals, which will produce thermal expansion and contraction phenomenon at different temperatures. When the ambient temperature rises, the granite precision platform is heated and expanded, and the size of the platform will change slightly. When the temperature drops, it will shrink back to its original state. Seemingly small size changes can be magnified into key factors affecting measurement results in precision measurement scenarios.
Taking the common coordinate measuring instrument matching granite platform as an example, in the high-precision measurement task, the measurement accuracy requirements often reach the micron level or even higher. It is assumed that at the standard temperature of 20℃, the various dimensional parameters of the platform are in an ideal state, and accurate data can be obtained by measuring the workpiece. When the ambient temperature fluctuates, the situation is very different. After a large number of experimental data statistics and theoretical analysis, under normal circumstances, the environmental temperature fluctuation of 1℃, the linear expansion or contraction of granite precision platform is about 5-7 ×10⁻⁶/℃. This means that for a granite platform with a side length of 1 meter, the side length may change by 5-7 microns if the temperature changes by 1 ° C. In precision measurements, such a change in size is sufficient to cause measurement errors beyond the acceptable range.
For the measurement work required by different accuracy levels, the influence threshold of temperature fluctuation is also different. In ordinary precision measurement, such as the size measurement of mechanical parts, if the allowable measurement error is within ±20 microns, according to the above expansion coefficient calculation, the temperature fluctuation needs to be controlled within the range of ± 3-4 ℃, in order to control the measurement error caused by the platform size change at an acceptable level. In areas with high precision requirements, such as the lithography process measurement in semiconductor chip manufacturing, the error is allowed within ±1 micron, and the temperature fluctuation needs to be strictly controlled within ± 0.1-0.2 ° C. Once the temperature fluctuation exceeds this threshold, the thermal expansion and contraction of the granite platform may cause deviations in the measurement results, which will affect the yield of chip manufacturing.
In order to deal with the influence of ambient temperature fluctuation on the measuring precision of granite precision platform, many measures are often adopted in practical work. For example, high precision constant temperature equipment is installed in the measuring environment to control the temperature fluctuation in a very small range; Temperature compensation is carried out on the measurement data, and the measurement results are corrected by software algorithm according to the thermal expansion coefficient of the platform and real-time temperature changes. However, no matter what measures are taken, the accurate grasp of the impact of ambient temperature fluctuations on the measurement accuracy of granite precision platform is the premise of ensuring accurate and reliable measurement work.
Post time: Apr-03-2025