Showing papers in "Materials protection in 1970"

Corrosion of metals in tropical waters, structural ferrous metals

Abstract: Corrosion data are reported for 20 structural ferrous metals exposed up to 16 yr in natural tropical waters, including seawater, fresh water and mean tide elevation. Time- corrosion curves derived from both weight loss and pitting are presented for many of the ferrous alloys and tabulated data for all metal environment combinations are included. These comprehensive long term results comprise the most extensive collection of accurate seawater and fresh water corrosion data presently available.

Effects of atmospheric sulfur dioxide on the corrosion of zinc

Abstract: THE AMOUNT OF SULFUR DIOXIDE IN THE AIR IS THE MAJOR FACTOR IN DETERMINING THE RATE OF CORROSION OF ZINC. BECOUSE LITTLE, IF ANY, ZINC CORROSION WOULD OCCUR IN A NONMARINE ENVIRONMENT IF SULFUR DIOXIDE WERE NOT PRESENT, THE REDUCED LIFE OF GALVANIZED PRODUCTS CAN BE DIRECTLY ATTRIBUTED TO AIR POLLUTION. /AUTHOR/

Corrosion of nickel alloys in quiet and low velocity seawater

Abstract: Two years of investigation of twenty-two commercially available nickel alloys was carried out to determine the relationship between corrosion resistance and type and quality of alloying elements. Tests were also made to determine the relationship of velocity of seawater and corrosion. Types of corrosion classified in the tests were: general corrosion, such as pitting, crevice corrosion, and stress corrosion. Test procedures described. Results were discussed, including data tables of corrosion rating and damage, plus properties of the alloys. Alloys classified according to rates and types of corrosion. No absolute conclusions were formed as to the metal content and corrosion resistance.

Adhesion fundamentals and methods of testing organic coatings

Abstract: CHEMICAL AND PHYSICAL FORCES RESPONSIBLE FOR ADHESION OF COATINGS TO VARIOUS SUBSTRATES, INCLUDING OTHER COATINGS, ARE DISCUSSED. GOOD ADHESION IS CONCEDED TO BE ESSENTIAL FOR GOOD PERFORMANCE OF A COATING IN MOST INDUSTRIAL APPLICATIONS, EXCEPT STRIPPABLE COATINGS. A GOOD COATING SYSTEM INVOLVES: (1) PREPARING THE SURFACE PROPERLY, (2) SELECTING A COATING WITH PROPERTIES PERMITTING IT TO ADHERE TO THE PREPARED SURFACE OF THE SUBSTRATE MATERIALS SO THEIR BEST ADHESIVE PROPERTIES ARE REALIZED, AND (4) APPLYING THE COATING SO THAT IT CAN ACHIEVE GOOD ADHESION. SURFACE PREPARATION METHODS ARE DESCRIBED TO IMPROVE ADHESION BETWEEN METALS TO COATINGS AND COATINGS TO COATINGS. PRIMERS ARE DESCRIBED WHICH ARE USED TO GET GOOD ADHESION BETWEEN A TOP COAT AND A METAL. OTHER FACTORS NEEDED TO OBTAIN GOOD ADHESION ARE DISCUSSED: (1) PIGMENTS AIDING ADHESION, (2) SOLVENTS, (3) CURING PROCEDURES, AND (4) INHERENT PROPERTIES. THE FOLLOWING REASONS ARE DISCUSSED FOR POOR ADHESION: (1) POOR SURFACE PREPARATION, (2) CONTAMINATION, (3) POOR APPLICATION TECHNIQUES, (4) POOR FORMULATION, 75) INCOMPATIBILITY, AND (6) ENDOSMOSIS AND ELECTROENDOMOSIS. THE FOLLOWING TEST EQUIPMENT USED TO MEASURE ADHESIONS ARE DESCRIBED: (1) PEEL TESTS, (2) MODIFIED PEEL TEST, (3) THE NACE X KNIFE ADHESION TEST, (4) ASTM D2197-68, TENTATIVE METHODS OF TEST FOR ADHESION OF ORGANIC COATINGS, (5) SCRAPE ADHESION TEST, (6) PARALLEL GROOVE TESTS, (7) SCRATCH TEST, (8) HESIOMETER, (9) PARALLEL SCRATCH TESTS, (10) WHIRLING BALL TESTS, (11) DISPENSIBILITY TESTS, (12) TWISTING CORK TEST, AND (13) ADHESIVE TAPE TEST. ADHESION TESTS APPEAR TO BE ESSENTIALLY SUBJECTIVE. AN ABSOLUTE CRITERION IS LACKING AGAINST WHICH A TEST MAY BE COMPARED.

Experience with titanium structures in marine service

Abstract: Properties are given for titanium used in corrosive environments, with description of cause and effects of biofouling, dissimilar metals, crevice corrosion, fatigue and design deficiencies Test data includes information on: resistance in the effect of antifouling paint on the corrosion resistance of the base metal, compatibility of titanium in reference to galvanic series of metal alloys in flowing seawater, immunity of titanium from pitting corrosion in brine solutions, and fatigue crack growth rate under strain in seawater environment Testing techniques described

Plastic tapes: 20 years of underground corrosion control

Abstract: PLASTIC TAPES MEET THE SAME CHEMICAL AND PHYSICAL PERFORMANCE REQUIREMENTS AS ENAMELS AND OTHER COATINGS. PLASTIC TAPES ARE BEING USED EXTENSIVELY TO PROTECT STEEL PIPELINES UNDERGROUND. DISCUSSION OF TAPE'S PROPERTIES, HISTORY, AND A SERIES OF COMPARISONS WITH OTHER COATINGS IS PRESENTED. /AUTHOR/

Coal tar enamel coatings for underground pipelines

Abstract: COAL TAR ENAMEL IS AN EFFECTIVE COATING TO PROTECT STEEL PIPELINES THIS COATING, BEING THERMOPLASTIC, IS EASILY APPLIED AND LENDS ITSELF TO FIELD USE IT HAS THE ADDED ADVANTAGES OF BEING ECONOMICAL IN BOTH COST AND APPLICATION /AUTHOR/

Performance of various coating systems in a marine environment

Abstract: TESTS WITH COATED STEEL PANELS THAT WERE IMMERSED, SEMI- IMMERSED, AND EXPOSED AT THE SPLASH ZONE LEVEL IN A MARINE ENVIRONMENT ARE DISCUSSED. PERFORMANCE OF THE COATINGS TESTED WAS NOTED ON VARIOUS SURFACE PREPARATIONS. DATA ARE RELATED TO COMPARATIVE COSTS, MAKING ECONOMIC EVALUATION POSSIBLE. /AUTHOR/

Seawater corrosion measurement - experimental probes

Abstract: SPECIAL EXPERIMENTAL CORROSION PROBES WERE DEVELOPED TO CONTINUOUSLY MEASURE GALVANIC AND CREVICE CORROSION. THE PROBES WERE EVALUATED IN THREEE SALINE WATER ENVIRONMENTS AT TEMPERATURES TO 150 C (302 F) AND SALINITIES TO 20%. A DISCUSSION OF THE PROBES AND THE DATA OBTAINED DURING THE EVALUATION ARE PRESENTED. /AUTHOR/

Plastic film coatings - marine fouling and corrosion prevention

Abstract: SARAN AND POLYETRAFLUOROETHYLENE (TFE) FILMS, WITH A PRESSURE SENSITIVE ADHESIVE, WERE APPLIED OVER THE SURFACES OF PAINTED AND UNPAINTED CARBON STEEL PANELS, UNPAINTED STAINLESS STEEL PANELS, AND K-MONELS PANELS. THE PANELS WERE SUBMERGED IN SEAWATER TO DETERMINE IF PLASTIC FILM COVERINGS CAN BE EFFECTIVELY USED TO PROTECT PAINTED AS WELL AS UNPAINTED METAL SPECIMENS FROM FOULING AND CORROSION, TO REMOVE MARINE GROWTH THAT BECOMES ATTACHED TO THE PLASTIC FILM SIMPLY BY STRIPPING OFF THE COVERING, AND TO PROLONG THE FOULING FREE AND CORROSION FREE INTERVALS SO AS TO DECREASE TOTAL EFFORT REQUIRED FOR RECONDITIONING FOULED OR CORRODED SURFACES. RESULTS OF THESE TESTS ARE PRESENTED. /AUTHOR/

Zinc-rich coatings for marine application

Abstract: ZINC-RICH COATINGS ARE GENERALLY TOUGH AND ABRASION RESISTANT. PROTECTION OF THE SUBSTRATE FUNCTIONS AS A BARRIER, AND AS HEAVY ZINC COATING LOADING IMPARTS CATHODIC PROTECTION. ADDITIONAL PROTECTION MAY BE ACHIEVED BY TOPCOATING. SOME ZINC INORGANICS HARDEN BY POST-CURING WITH ACID; OTHERS SELF-CURE. THE CHARACTERISTICS OF ZINC-RICH COATINGS AND METHODS OF APPLICATION ARE DESCRIBED. /AUTHOR/