THERE ARE SOME METHODS TO DEPOSIT THIN FILMS ON THE INTERNAL WALLS OF CYLINDRICAL BODIES WHICH THE BEST OF THEM IS A CYLINDRICAL SPUTTERING CATHODE. IN THIS RESEARCH, FOR THE FIRST TIME WE HAVE USED A CYLINDRICAL UN- COOLED CATHODE WITH CONSTANT OUTSIDE MAGNETRON TO DEPOSIT A THIN COPPER FILM ON THE INTERNAL WALL OF A STEEL CYLINDER. THE RATE OF DEPOSITION WAS 30 A/SEC. IN THIS EXPERIMENT, A CYLINDRICAL COPPER BAR WITH SUITABLE DIAMETER USED AS THE CATHODE AND STEEL HALLOW CYLINDER CONCENTRIC TO IT AS THE ANODE. THE BASE PRESSURE WAS 6.7×10-5MBAR AND THE ARGON PRESSURE CONSTANT AT 1.1×10-2 MBAR THROUGHOUT THE EXPERIMENT. IN THIS PAPER, FIRST THE PHYSICS OF CYLINDRICAL SPUTTERING IS DESCRIBED IN BRIEF AND THEN THE EXPERIMENT OF THIN FILM DEPOSITION BY CYLINDRICAL MAGNETRON CATHODE AND ITS RESULTS ARE EXPLAINED. FINALLY THE CONCLUSIONS ARE EXPRESSED.

SINCE THE BEGINNING OF THE 20TH CENTURY, IMPLEMENTATION OF ARMED CONCRETE WAS SUGGESTED AS A CHOICE IN CONSTRUCTION PROJECTS. THE FEATURES OF HIGH STRENGTH, LONG LIFESPAN, EASE OF IMPLEMENTATION AND ALSO BEING ECONOMIC (COMPARED TO STEEL STRUCTURES ESPECIALLY AFTER WORLD WAR TWO AND THE LACK OF IRON) HAS CAUSED THE ARMED CONCRETE TO HAVE A VAST APPLICATION RANGE. IN MOST OF THESE APPLICATION CASES, THE STEEL ARMATURE OF CONCRETE WERE DURABLE WITH NO PROBLEM, SO IT IS OBVIOUS THAT THE CHANGE IN ENVIRONMENTAL CONDITIONS CAN CREATE SERIOUS DAMAGES CAUSED BY THE EROSION OF STEEL IN SOME CONCRETE STRUCTURES AND CONSTRUCTIONS. IF THE ALKALINE ENVIRONMENT CREATED WITHIN CONCRETE BECAUSE OF CEMENT HYDRATION THAT PROTECTS THE STEELS WITHIN THE ARMED CONCRETE FROM EROSION FADES BECAUSE OF SALT POLLUTION (AND CHLORIDE ATTACK), THE STEEL ARMATURE OF CONCRETE WILL FACE EROSION. THESE FACTORS IN FACT DETERMINE THE ELECTROCHEMICAL CONDITIONS THAT START THE EROSION PROCESS. IN ORDER TO STOP OR PREVENT THE EROSION FROM HAPPENING, A LOW CURRENT CAN BE PASSED THROUGH THE STEEL SO THAT THE ELECTRICAL POTENTIAL NEEDED FOR EROSION CAN BE OBTAINED IN NO PARTS OF THE STEEL ARMATURE. TODAY, THIS METHOD IS KNOWN AS THE CATHODE PROTECTION OF THE STEEL IN ARMED CONCRETE USED FOR MARITIME STRUCTURES WITHIN AN EROSIVE ENVIRONMENT, BECAUSE OF THE EXISTENCE OF CHLORIDE ION, DRY AND WET CYCLES, HIGH LEVELS OF HUMIDITY AND TEMPERATURE. THIS METHOD IS CONSIDERED AS A PROVED STRATEGY AND ITS INSTRUCTIONS AND PRINCIPLES ARE EXPLAINED IN INTERNATIONAL STANDARDS.

IN THIS RESEARCH, A HOT CATHODE PLASMA SOURCE WAS MADE AND THE PLASMA FORMATION IN HIGH VACUUM REGIME (RANGE OF 10-3 TO 10-4 MBAR) WAS STUDIED BY APPLYING MAGNETIC FIELD BY MEANS OF PERMANENT MAGNETS ASSEMBLY. EFFECTS OF VARIOUS CONTROL PARAMETERS SUCH AS WORKING PRESSURE, DISCHARGE VOLTAGE AND EXTERNAL ELECTRON SOURCE (HOT TUNGSTEN FILAMENT) ON PLASMA DENSITY WERE INVESTIGATED. AT A DISCHARGE VOLTAGE OF 57 VOLT, MAGNETIC FIELD OF ABOUT 200 GAUSS, FILAMENT CURRENT OF 18 AMPERE, 130 MILIAMPERE FOR DISCHARGE CURRENT WAS OBTAINED AT A PRESSURE OF 1.2×10-4 MBAR.

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