Monel

About: Monel is a research topic. Over the lifetime, 573 publications have been published within this topic receiving 4478 citations. The topic is also known as: Monel metal.

Enhanced tensile strength for electrodeposited nickel-copper multilayer composites

Abstract: The tensile strength of electrodeposited layered composites of the nominal overall composition 90 pct Ni-10 pct Cu is shown to increase sharply to the 1300 MPa range as the thickness of the Cu layers is decreased below ~0.4 ώm. This tensile strength value is almost a factor of three greater than that measured for Ni itself, and more than a factor of two greater than the handbook value for Monel 400.

X‐Ray Photoelectron Spectroscopic Study of the Aqueous Oxidation of Monel‐400

Abstract: The surface of Monel-400 alloy was exposed to high pH, aqueous corrosion at 285~ under both oxidizing and reducing conditions. After exposures lasting from 0.3 to 335 hr the surfaces were examined by x-ray photoelectron spectroscopy, scanning electron microscopy, and other techniques. Under reducing conditions, no corrosion film forms on the metal surface, but under oxidizing conditions, the first corrosion layer which forms at the solution interface is entirely Ni(OH)2. This hydroxide, which persists for long times at pH ,.~ 10 but which rapidly converts to NiO at pH ,., 14, is shown to result from a Precipitation process. The composition of the corrosion film is determined by the relative solubilities of nickel and copper at the interface. A composition profile of the corrosion layer beneath the outermost film shows :a gradual increase in cuprous ion concentration with increasing depth, probably due to solid-state migration. This suggests that the aqueous corrosion of Monel-4O0 involves both solid-state oxide growth and an ionic dissolution and precipitation mechanism.

Nature and evolution of the fusion boundary in ferritic-austenitic dissimilar weld metals : Part 1 - Nucleation and growth

Abstract: A fundamental investigation of fusion boundary microstructure evolution in dissimilar-metal welds (DMWs) between ferritic base metals and a face-centered-cubic (FCC) filler metal was conducted. The objective of the work presented here was to characterize the nature and character of the elevated-temperature fusion boundary to determine the nucleation and growth characteristics of DMWs. Type 409 ferritic stainless steel and 1080 pearlitic steel were utilized as base metal substrates, and Monel (70Ni-30Cu) was used as the filler metal. The Type 409 base metal provided a fully ferritic or body-centered-cubic (BCC) substrate at elevated temperatures and exhibited no on-cooling phase transformations to mask or disguise the original character of the fusion boundary. The 1080 pearlitic steel was selected because it is austenitic at the solidus temperature, providing an austenite substrate at the fusion boundary. The weld microstructure generated with each of the base metals in combination with Monel was fully austenitic. In the Type 409/Monel system, there was no evidence of epitaxial nucleation and growth as normally observed in homogeneous weld metal combinations. The fusion boundary in this system exhibited random grain boundary misorientations between the heat-affected zone (HAZ) and weld metal grains. In the 1080/Monel system, evidence of normal epitaxial growth wasmore » observed at the fusion boundary, where solidification and HAZ grain boundaries converged. The fusion boundary morphologies are a result of the crystal structure present along the fusion boundary during the initial stages of solidification. Based on the results of this investigation, a model for heterogeneous nucleation along the fusion boundary is proposed when the base and weld metals exhibit ferritic (BCC) and FCC crystal structures, respectively.« less