Ualloy-4J29 also known as Kovar alloy. it was invented to meet the need for a reliable glass-to-metal seal, which is required in electronic devices such as light bulbs, vacuum tubes, cathode ray tubes, and in vacuum systems in chemistry and other scientific research.
Ualloy-4J29was invented to meet the need for a reliable glass-to-metal seal, which is required in electronic devices such as light bulbs, vacuum tubes, cathode ray tubes, and in vacuum systems in chemistry and other scientific research. Most metals cannot seal to glass because their coefficient of thermal expansion is not the same as glass, so as the joint cools after fabrication the stresses due to the differential expansion rates of the glass and metal cause the joint to crack.
Mainly used in electric vacuum components and emission control, shock tube, igniting tube, glass magnetron, transistors, seal plug, relay, integrated circuits lead, chassis, brackets and other housing sealing.
Tensile Strength, MPa
Code of condition
Typical Physical properties
Electrical resistivity at 20ºC(mm2/m)
Temperature factor of resistivity(20ºC~100ºC)X10-5/ºC
Curie point Tc/ ºC
Elastic Modulus, E/ Gpa
Q1.Is there any discount of the wire?
A. Yes. Bigger quantity will get a discount.
Q2.Information needed if I want a quotation?
A Name, Standard, Material Grade(Chemical Composition), Size Quantity, Weight.
Q3. Can we visit your company/factory before place the order?
A. Yes. Welcome anytime
Q4: How does your factory do regarding quality control?
A. Quality is priority. We always attach great importance to quality controlling from beginning to end.