TECHNICAL DOC--HOW Sericite Mica is Used in Welding Material

taking avantage of large mica reserve, Chenxing assures stable and consistent mica production and supply Size:5-1250mesh

E4303,E4313 welding rod is the key product of welding materials made in China, which account for about 80% of the total welding rod production. In recent years, the welding industry are seeking for lower cost material to substitute titanium dioxide and rutile etc, sepiolite, white clay, pyrophyllite etc siliceous nonmetallic minerals are effectively used in E4303, E4313 welding rod, while they have not so smooth and plasticity. The comprehensive properties of sericite mica are better and are more effective to increase the quality of welding rod.

Sericite Mica is a kind of flake shape aluminium potassium silicate, formula is KAl2[Si3AlO10](OH,F), the chemical contents that are suitable for welding rod are:

SiO2	Al2O3	K2O	H2O	S	P
50-60%	25-30%	7-11%	<5%	<0.03%	<0.03%

Sericite Mica Applied Function and Features

Compared with sepiolite, white clay, pyrophyllite, sericite mcia contains more K2O ( pyrophyllite, 7.41%, sericite mica, 7.5-11%, white clay, sepiolite, no content of K2O), so it has lower ionized electric potential, when the electric arc are burning, it apt to provide electro conductive ions and make electric arc burn stably.

Sericite Mica contain less S, P etc impurities (S: 0.015 – 0.018%), it apt to reduce the content of S, P in the metal, and reduce the possibility of metal crack and increase its cracking resistance.

Lower water absorption and expansion rate ( pyrophyllite, 70.5%; sepiolite, 5.2%; Titanium dioxide, 32.6%; sericite mica, 4.3%), to reduce welding rod shell flaw.

Lower content of absorbed water (100 °Cx2h drying, water content: pyrophyllite, 1.8%; white clay, 5.2%; sepiolite, 5.8%; titanium dioxide, 2.4%; sericite mica, 2.5%), sericite mica can increase vapor resistance, reduce and combine the dispersed hydrogen, decrease porous sensibility.

Due to its fine flake shape, sericite mica has certain flexibility, plasticity, and can increase the smooth of welding rod coating and the flowability in filler powder tank and improve its pressed coating capability.

Sericite Mica has even particle distribution, no oversize granular, when electric arc burns no explosion occurs, so the splash is reduced and burning sound is decreased.

    Conclusion: Sericite mica is the newstyle shelling material for welding rod, it contains 9% -11% K2O, can increase the stability of electric arc and solve the problem of rod shell frequent cracks effectively. The mix percentage is 3% to 5% when it is used in E4303, E4313 etc acid welding rod, sericite mica can increase the coatings smooth and adhesion, ideal substitute for titanium dioxide and reduce the production cost.

TECHNICAL DOC--HOW Sericite Mica is Used in Welding Material