JoudCo Steel product range covers rebar grades produced in conformance with the requirements of following standards :
- Syrian Standard 1642 Part 2 : Grade 400W.
- ISO 6935-2 : Grades : RB 400W , RB 500W.
- DSTU 3760 : Grade GOST A500 C.
- ASTM A 615 : Grade 60.
- BS4449 : 1997 - Grade 460 B.
Bar Quenching :
JoudCo Steel has introduced Bar Quenching Process for manufacturing superior quality reinfocing bars with improved yield strength and weld ability.To avoid those draw backs of exsisting method the installation of "Thermex" quenching process has been installed , which makes possible to produce high yield strength concerte-reinforcing bars. with improved weld ability in economic conditios, without the addition of any expensive additives of further working processes.
The cooling system we are using has been extensively implemented since 1972 by several major steel industries in Europe , North & South America and Asia and has proved itself as the most effecient and reliable one . In this process the rebar properties are attained by regulating the microstructure thus enabling the use of lower carbon and manganese content. Lower alloy content gives better rebar ductility and enhance weld ability.
The quenching produces a composite microstructure with strong tempered rim and ductile core , through low air cooling temperature that results a thin and compact mill scale on the rebar surface. Quality activities of JoudCo Steel are controlled and monitored from the begining to finished products till it is dispatched and reached to the customers.
In the conventional Hot Rolling Properties are achieved by regulating the chemical composition. Use of higher carbon and manganese content though , increases the strength but may impair rebar ductility and / or weld ability. The slow air-cooling results in a thick but flacky Mill Scale layer on the rebar surface. The microstructure of the rebar's is ferrite-paralytic , typical of any medium carbon steel.
Bar Quenching Process :
In Bar Quenching Process , the rebar properties are attained by regulating the microstructure thus enabling the use of lower carbon and manganese contents.Lower alloy content gives better rebar ductility and good weld ability. The quenching produces a composite microstructure with a strong tempered marten site ring and a ductile core. Combination of these structures gives the quenched rebar high yield strength and good ductility. Air-cooling from lower temperatures results in a thin and compact mill scale on the rebar surface.
Discoloration Behaviour :
The early discoloration of ISPF Quenched steel rebar is due to the thin mill scale layer formed becaue the hot rebar contacts with the Thermex water.After discoloration, the surface of the quenched steel rebar remains smooth. Conventional hot-rolled rebar's having thick mill scale on the surface,although initially resist the discoloration , but later ( in a course of time ) it will also be discolored.