Division 01 — Metallurgical / Non-Ferrous / Copper

Copper Treatment

Copper treatment is the chemical treatment of molten copper and copper alloys (bronze, brass) — covering fluxes, deoxidisers, and degassing — to prevent oxidation, remove dissolved gas, and protect the melt for clean pours.

CFC Egypt manufactures a targeted range of copper treatment products — EGYFLUX CU copper fluxes and EGYTAB CU degassing tablets — specifically formulated for the oxidation and gas challenges of copper-alloy melting. Copper is one of the most reactive molten metals in common foundry use: it absorbs hydrogen readily from atmospheric moisture and from moulding materials, and its surface oxidises rapidly to form cuprous oxide if left unprotected. Our EGYFLUX CU flux range provides effective melt surface coverage and oxidation prevention across the principal copper alloy families — including tin bronze, gunmetal, brass, and aluminium bronze — while EGYTAB CU delivers controlled, consistent degassing before each pour.

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Domaines d'utilisation

Copper alloy castings are used wherever corrosion resistance, wear resistance, and electrical or thermal conductivity are required. CFC copper treatment chemistry supports foundries across the following sectors.

Marine & Naval Fittings

Propellers, propeller hubs, sea valves, and through-hull fittings are cast in tin bronze and aluminium bronze for their resistance to seawater corrosion. Marine castings must be pressure-tight and free of gas porosity — a single gas void in a sea valve or hull fitting is a safety defect. Degassing with EGYTAB CU before each pour, combined with effective flux cover throughout the melting and holding period, is standard practice in marine bronze foundries producing to classification society standards.

Pumps, Valves & Fittings

Bronze and brass pump casings, impellers, gate valves, ball valves, and pipe fittings for water, gas, oil, and chemical service are among the highest-volume copper alloy castings. Pressure integrity is non-negotiable; clean, porosity-free metal — achieved through proper flux and degassing treatment — is the primary requirement. Valves and fittings destined for certification to international pressure vessel standards require documented melt treatment as part of process control records.

Electrical & Power Engineering

High-conductivity copper castings for busbars, switch contacts, current-carrying components, and electrical connectors require very clean metal with minimal oxide and gas inclusions that would reduce electrical conductivity and mechanical strength at connection points. Effective flux coverage and degassing to eliminate oxide inclusions and gas porosity are critical for electrical-grade copper castings, where conductivity specification tolerances are tight.

Bearings & Wear Parts

Phosphor bronze and gunmetal bearings, bushings, worm wheels, and wear plates are cast for industrial machinery, marine gearboxes, and hydraulic systems. Sound internal structure — free of gas porosity and oxide inclusions — is essential for bearing castings, where subsurface defects accelerate fatigue failure under load and reduce service life. Consistent melt treatment with copper flux and degassing tablets ensures the metal cleanliness required for load-bearing copper alloy components.

Decorative & Architectural Bronze

Architectural bronze and decorative brass castings — door furniture, railings, plaques, sculptures, and commemorative pieces — require clean, defect-free surfaces with consistent colour and texture. Gas porosity, oxide inclusions, and zinc-loss pitting are the main quality defects that spoil decorative castings. Proper flux coverage minimises dross entrainment and zinc vapour loss, while degassing prevents the subsurface gas blisters that appear as pitting after polishing or patination.

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CFC Aluminium Treatment Products

EGYFLUX CU copper fluxes — available in four grades for different alloy types and temperature ranges — and EGYTAB CU degassing tablets. All manufactured in Sadat City, Egypt.

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Questions fréquemment posées

Technical questions on copper alloy flux treatment and degassing answered plainly. For a product recommendation matched to your alloy and process, contact our technical team.

Copper treatment is the chemical treatment of molten copper and copper alloys (bronze, brass) — covering fluxes, deoxidisers, and degassing — to prevent oxidation, remove dissolved gas, and protect the melt for clean pours. Copper and its alloys are highly reactive when molten: they readily absorb hydrogen from atmospheric moisture and form cuprous oxide on the melt surface and within the casting. Covering fluxes applied to the melt surface prevent oxidation and capture oxide impurities; degassing tablets plunged into the melt remove dissolved hydrogen before pouring. Together, these treatments are the primary means of controlling melt quality in copper and copper-alloy foundries.

Without a covering flux, the surface of a copper, bronze, or brass melt oxidises rapidly, forming cuprous oxide (Cu2O) and a complex oxide skin. This oxide layer, if not removed before pouring, becomes entrained in the casting as non-metallic inclusions that reduce tensile strength, ductility, and pressure tightness. In brass melts, zinc evaporates rapidly at elevated temperatures, causing surface porosity and composition drift. A covering flux forms a molten protective layer on the bath surface that prevents contact with the atmosphere, captures oxide impurities in the slag phase for clean skimming, and — in brass — suppresses zinc vapour loss. Fluxing is an essential process step for any copper alloy foundry producing to engineering quality standards.

Copper alloys absorb hydrogen readily from moisture in the charge materials, crucibles, and the surrounding atmosphere. When the melt solidifies, this dissolved hydrogen precipitates as gas porosity. EGYTAB CU copper degassing tablets are plunged to the base of the melt using a steel rod immediately before pouring. The tablet releases gas that nucleates bubbles throughout the bath, scavenging dissolved hydrogen and carrying it to the surface where it escapes. Pre-measured tablets ensure consistent dosing for a given melt weight, avoiding the under-dosing or over-dosing variability of hand-added powder. Degassing is particularly important for pressure-rated castings — pump impellers, valve bodies, marine fittings — where gas porosity is a direct rejection criterion.

Bronze (copper-tin alloys, and copper-aluminium or gunmetal variants) and brass (copper-zinc alloys) share the fundamental requirements for oxidation prevention and degassing but have distinct sensitivities. Brass melts at lower temperatures than tin bronze and loses zinc rapidly by evaporation above about 950 °C — a flux cover that suppresses zinc vaporisation is especially critical for brass to maintain composition and prevent surface porosity. Tin bronze and gunmetal are generally more thermally stable but are sensitive to oxide inclusion and hydrogen pickup in the same way as other copper alloys. CFC EGYFLUX CU fluxes are available in multiple grades (CU, CU 500, CU 900, CU CR) to match the different temperature ranges and alloy compositions of the major copper alloy families. Contact us with your alloy grade for a specific recommendation.

CFC Egypt supplies two product types for copper treatment: copper fluxes (EGYFLUX CU, EGYFLUX CU 500, EGYFLUX CU 900, EGYFLUX CU CR) — covering and protective flux powders applied to the melt surface to prevent oxidation and capture impurities — and EGYTAB CU copper degassing tablets, plunged into the melt to remove dissolved hydrogen before pouring. The appropriate flux grade is selected based on alloy type, melting temperature, furnace size, and specific quality requirements. Contact our technical team for a recommendation matched to your process.

Parlez-nous

Ready to improve your copper alloy casting process?

Tell us your alloy grade (copper, bronze, brass, or gunmetal), your furnace type, your cast weight per heat, and your current quality issues — gas porosity, oxide inclusions, or zinc loss. Our technical team will recommend the right EGYFLUX CU flux grade and EGYTAB CU dosing rate for your specific operation.