Bonding of nickel alloys (Hastelloy B, Inconel 600 and Monel) was performed by means of the powder-pack method using the bonding powder which contains no SiC. The boride layer was analyzed using X-ray diffraction and EPMA. The high-temperature microhardness and friction and wear characteristics of bonded nickel alloys were investigated. The obtained results are as follows:
(1) Thick boride layers could be obtained without flaking in this study. The thickness of the layers was about 65∼75μm under the bonding conditions for 7.2ks at 1173K.
(2) The Knoop hardness of bonded Hastelloy B, Inconel 600 and Monel were 1650HK, 1580HK and 600HK, respesctively. The boride layers of nickel alloys mainly consisted of Ni2
B and Cu were also detected in the boride layers of Hastelloy B and Monel, respectively.
(3) The high-temperature microhardness of Hastelloy B and Inconel 600 were greatly improved by bonding. But bonding was ineffective for the high-temperature microhardness of Monel.
(4) The friction coefficients of bonded Hastelloy B and Inconel 600 against SUJ2 and SUS 304 indicated lower values than those of untreated materials, but a reduction in the friction coefficients was not recognized in Monel. This result was considered to be attributable to the precipitation of copper in the boride layer of Monel.
(5) The wear resistance of nickel alloys against SUJ2 and SUS 304 was improved by bonding.
(6) Bonding was effective for reduction of wear loss of the mating materials of Hastelloy B and Inconel 600, but it was ineffective for those of Monel.