Nickel aluminide coated low alloy stainless steel
    91.
    发明授权
    Nickel aluminide coated low alloy stainless steel 失效
    镍合金涂层低合金不锈钢

    公开(公告)号:US3762884A

    公开(公告)日:1973-10-02

    申请号:US3762884D

    申请日:1971-10-18

    申请人: NASA

    发明人: GRISAFFE S KLECHKE E

    摘要: Low alloy austenitic stainless steel is protected from oxidative corrosion and erosion at high temperatures in the presence of exhaust gases from internal combustion engines by flame-spraying a layer between about 0.003 inches and about 0.007 inches thick of an alloy of 80 percent nickel and 20 percent chromium on the steel base, and thereafter converting the layer to an intermetallic chromium containing nickel aluminide coating by a low temperature aluminum cementation process. A cementation pack comprising 96 percent aluminum oxide, 2 percent aluminum, 1 percent sodium chloride, and 1 percent ammonium bifluoride is placed on the nickel-chromium layer in an inert atmosphere for a period between four hours and 24 hours at 1400*F to 1600*F to form an intermetallic chromium containing nickel aluminide coating containing 40 to 60 atomic percent aluminum. The coated steel is highly resistant to oxidation corrosion and erosion by high temperature exhaust gases from internal combustion engines. It is particularly useful in the construction of thermal reactors for exhaust systems in automobiles for the control of pollution from exhausts.

    Chromizing process
    92.
    发明授权
    Chromizing process 失效
    染色工艺

    公开(公告)号:US3728149A

    公开(公告)日:1973-04-17

    申请号:US3728149D

    申请日:1970-08-06

    发明人: FORAND J WOO SHIN P

    IPC分类号: C23C10/02 C23C10/32 C23C9/00

    CPC分类号: C23C10/02 C23C10/32

    摘要: In a method of forming a corrosion resistant coating on steel strip, the strip is coated on at least one side with a uniform distribution of a chromium-containing metal powder and a considerably less amount of an alkali or alkaline earth metal halide. The powder, containing the halide, is compacted on the strip. The strip is coiled, preferably in a tight coil, and heated in a heating zone in a protective atmosphere for sufficient time and at a temperature to cause diffusion between the metal strip and metal powder, and to thus form a protective stainless steel coating on the strip.

    摘要翻译: 在钢带上形成耐腐蚀涂层的方法中,将带材涂覆在至少一侧,均匀分布含铬金属粉末和相当少量的碱金属或碱土金属卤化物。 含有卤化物的粉末在带上被压实。 带材卷绕,优选在紧密的卷材中,并且在加热区域中在保护气氛中加热足够的时间并且在一定温度下加热,以引起金属带和金属粉末之间的扩散,从而在其上形成保护性不锈钢涂层 跳闸。

    High temperature metallic diffusion coating and method
    93.
    发明授权
    High temperature metallic diffusion coating and method 失效
    高温金属扩散涂层和方法

    公开(公告)号:US3617360A

    公开(公告)日:1971-11-02

    申请号:US3617360D

    申请日:1968-11-29

    申请人: GEN ELECTRIC

    发明人: LEVINE DAVID J

    IPC分类号: C23C10/02 C23C9/02

    CPC分类号: C23C10/02

    摘要: Improved oxidation and sulfidation resistance can be imparted to a high-temperature metallic diffusion coating diffusion bonded with metallic surface, such as a nickel, cobalt or iron base alloy surface, by embedding in a coating outer portion between about 5 and 50 volume percent of oxide particles of up to about 20 microns in size and thermally stable to at least about 2000* F.