-
1.发明授权
公开(公告)号：US3764371A
公开(公告)日：1973-10-09
申请号：US3764371D
申请日：1970-11-18
发明人： BALDI A
CPC分类号： C23C10/60 , C23C10/38 , Y10T428/12861 , Y10T428/12944
摘要： RICH CHROMIUM DIFFUSION COATING ON TD NICKEL OR TD NICHROME IS OBTAINED IN ONE STEP BY EMBEDDING WORK IN CHROMIUM DIFFUSION COATING PACK CONTAINING NICKEL WITH OR WITHOUT SOME COBALT, AND HELD IN UNSEALED RETORT CUP AT LEAST 15 INCHES HIGH. MAGNESIUM HALIDE IS HELPFUL TO HAVE IN THE PACK AND PACK CAN ALSO CONTAIN METALLIC IRON TO REDUCE COATING TEMPERATURE. MASKING IS ARRANGED BY COVERING THE SITES TO BE MASKED WITH A LAYER OF A MIXTURE OF NICKEL POWDER AND INERT FILLER. FOR BETTER HIGH TEMPERATURE OXIDATION RESISTANCE THE CHROMIUM-RUCH COATING IS COVERED BY AN ALUMINUM DIFFUSION COATING FROM A SIMPLE ALUMINUM DIFFUSION PACK OR ONE THAT HAS THE ALUMINUM MIXED WITH CHROMIUM. LOW TEMPERATURE ALUMINUM DIFFUSION IS MORE UNIFORM WHEN PACK ENERGIZER IS ALUMINUM CHLORIDE OR OTHER MATERIAL THAT DOES NOT GENERATE NITROGEN. A MANGANESE-CONTAINING ALUMINIZING PACK GIVES BETTER PROTECTION THAN A SIMPLE ALUMINIZING PACK, PARTICULARLY AGAINST MARINE CORROSION, AND WHEN THERE IS A CONVERSION COATING APPLIED OVER THE ALUMINIZING. CONVERSION COATING MIXTURE WETS ALUMINIZED FERROUS SURFACE BETTER WHEN THE BLACK IS THEN REMOVED WITH THE HELP OF NITRIC ACID. ALUMINIZED SUPERALLOY CAN BE HEATED IN AIR TO WHITEN IT, THEN CLEANED TO GIVE PRODUCT HAVING MORE ADHERENT CASE. ALSO ADDING SOME LANTHANUM OR YTTRIUM TO SUPERALLOY LIKE WI 52 GIVES BETTER HIGH TEMPERATURE RESISTANCE.
-
公开(公告)号：US3785854A
公开(公告)日：1974-01-15
申请号：US3785854D
申请日：1972-05-18
发明人： BALDI A
CPC分类号： C23C22/74 , C23C10/60 , Y02T50/67 , Y10S428/938 , Y10T428/12743 , Y10T428/12854
摘要： Rich chromium diffusion coating on dispersion-strengthened nickel or nichrome is obtained in one step by embedding work in chromium diffusion coating pack containing nickel with or without some cobalt, and held in unsealed retort cup at least 15 inches high. Pack can also contain metallic iron to reduce coating temperature. Masking is arranged by covering the sites to be masked with a layer of a mixture of nickel powder and inert filler. For better high temperature oxidation resistance the chromium-rich coating is covered by an aluminum diffusion coating from a simple aluminum diffusion pack or one that has the aluminum mixed with chromium. Low temperature aluminum diffusion is more uniform when pack energizer is aluminum chloride or other material that does not generate nitrogen, and gives good protection against marine corrosion of steels, and particularly when there is a chromate-type coating applied over the aluminizing. Highly effective chromate-type coating mixture consists essentially of aqueous solution of chromic and phosphoric acid also containing magnesium salts of said acids and dispersed polytetrafluoroethylene particles. Aluminized superalloy can be heated in air to whiten it, then cleaned to give product having more ductile case. Such coated superalloy can also be stripped of coating by aqueous HNO3-HF-CrO3 bath.
-
公开(公告)号：US3801357A
公开(公告)日：1974-04-02
申请号：US3801357D
申请日：1972-01-20
发明人： BALDI A
摘要： Diffusion coating of superalloys with aluminum is effectively prevented at desired locations by masking with nickel or cobalt aluminide having less than one atom of aluminum for each atom of nickel or cobalt, and packed against those locations. Chromium, silicon, iron or any combination of them can be coated along with the aluminum as by alloying with the aluminum used to provide the coating, and particularly effective particle size of such alloys is about 1 micron. Such sizes are produced by simultaneous magnesothermic reduction. Molybdenum and tungsten silicide particles can also be produced in this small size by such reduction and make effective diffusion coating materials. Diffusion coating can also be confined to restricted portions of work pieces without the above masking.
-
-
搜索结果
3 条记录 (耗时 0.011 秒)
