Frequently Asked Questions
Q - What is the maximum watt density of your heaters?.
A - a. ) The maximum watt density is controlled by the maximum temperature the element can maintain without degrading. In the case of the mica heater, the element can withstand a maximum temperature of 250ºC (482ºF) In the case of free convection in air, the heaters can produce 1 W/cm2 (~6.5 W/in2) without exceeding this temperature. If the heater is in contact with a heat sink this Watt density can be increased.
b.) Metal heaters have a maximum recommended temperature of 230ºC (446ºF). In this case, because the element is in intimate contact with a metal substrate, much more heat can be transmitted without the temperature increasing dramatically. In addition, because the heater is usually used to heat water, a significant amount of heat can be transferred without the heater surpassing the maximum recommended temperature. Metal heaters with Watt Densities of 40W/cm2 (258 W/in2) have successfully passed life tests in boiling water applications at Datec.
Q - What is the maximum temperature for your heaters?
A - a.) Mica: 250 ºC (482ºF)
b.) Metal: 230 ºC (446ºF)
Q - On what materials can you print your heaters?
A - a.) Mica based heaters are printed on mica sheets that can be made with various thicknesses ranging from 0.4 mm to 1.0 mm (0.016 – 0.040”) although 0.5 mm (0.020”) is the most common thickness.
b.) Metal based heaters have been successfully printed on Aluminum, Stainless Steel (type 304) and Carbon Steel.
Q - Is your element touchproof?
A - a.) Mica heaters are touchproof on the mica side of the substrate. The side covered with PTFE (Teflon®) can be placed against a non-conductive material. For applications requiring a touch proof top-coat, the Teflon can be replaced with a proprietary touchproof coating.
b.) Metal based heaters can be made with or without a touchproof topcoat depending on the requirement of the application.
Q - How do you connect your heaters?
A - a.) Mica heaters are connected with connectors or leads riveted into the mica sheet substrate.
b.) Metal heaters are connected with connectors or leads soldered onto the heater.
Q - What is the maximum continuous working temperature for your ceramic coatings?
A - While many ceramic coatings have maximum temperature capabilities in excess of 600 ºC, the main issue at elevated temperatures is maintaining the adhesion of the coating to the substrate. If you have an application for a high temperature coating, please contact our Sales department.
Q - How hard are your wear resistant coatings?
A - Hardness of coatings is difficult to measure because of the very thin nature of the coating and the hardness of the substrate can affect the reading. Datecs ceramic coatings are measured with a nano hardness indenter which provides an accurate measurement of the hardness of the coating without being influenced by the substrate. In addition the nano-hardness indenter can provide Young's modulus data for the coating. The nano-hardness indenter provides data in MPa.
Q - What is the typical thickness of your coatings?
A - Typical thicknesses range from 10-50 µm (0.0002”-0.002”)
Q - What is the coefficient of Friction of your non-stick coating?
A - Typical Coefficient of Friction of our non-stick coatings is 0.1 static and 0.06 kinetic when measured against polyethylene.
Q - What chemicals can your corrosion coatings withstand?
A - Some of Datec’s coatings have been designed to withstand attack from hydro-chloric and hydro-fluoric acids. If you have a specific corrosive environment that requires a coating, please contact our Sales department for more information.
Q - What is the thermal conductivity of your ceramic coatings?
A - Thermal conductivity is a function of temperature and can vary significantly over the temperature range that ceramic coatings may be exposed to. Some typical materials are shown below:
Thermal Conductivity
20 ºC 500 ºC
i. Alumina: 33 11
ii. Zirconia: 1.7-2.2
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