Electroless plating preparation and microwave electromagnetic properties of Ni-coated carbonyl iron particle/epoxy coatings

This paper investigated the effects of silicone oil viscosity (SOV) and carbonyl iron particle (CIP) weight fraction and size on dynamic yield stress for magnetorheological (MR) grease. The MR grease samples were prepared using orthogonal array L9 on the basis of a new preparation technology. The shear rheological tests were undertaken using a rotational shear rheometer and yield stress was obtained based on the Bingham fluid model. It was found that CIP fractions ranging from 65 wt% to 75 wt% and SOV varying from 50 m2·s−1 to 1000 m2·s−1 significantly affect the magnetic field-dependent yield stress of MR grease, but the CIPs with sizes of 3.2–3.9 μm hardly had any influence based on the analysis of variance (ANOVA). In addition, the yield stress of MR grease mainly depended on the CIP fraction and SOV by comparing their percent contribution (PC). It was further confirmed that there were positive effects of CIP fraction and SOV on yield stress through response surface analysis (RSA). The results showed a high dynamic yield stress. It indicated that MR grease is an intelligent material candidate which can be applied to many different areas requiring high field-induced rheological capabilities without flow for suspension. Moreover, based upon the multivariate regression equation, a constitutive model was developed to express the function of the yield stress as the SOV and fraction of CIPs under the application of magnetic fields.

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Greatly enhanced microwave absorbing properties of planar anisotropy carbonyl-iron particle composites

Journal of Magnetism and Magnetic Materials ◽

10.1016/j.jmmm.2014.09.015 ◽

2015 ◽

Vol 375 ◽

pp. 100-105 ◽

Cited By ~ 42

Author(s):

Liang Qiao ◽

Rui Han ◽

Tao Wang ◽

Liyun Tang ◽

Fashen Li

Keyword(s):

Carbonyl Iron ◽

Iron Particle ◽

Planar Anisotropy ◽

Microwave Absorbing Properties ◽

Carbonyl Iron Particle ◽

Microwave Absorbing

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Zirconia-coated carbonyl-iron-particle-based magnetorheological fluid for polishing optical glasses and ceramics

Applied Optics ◽

10.1364/ao.48.006797 ◽

2009 ◽

Vol 48 (35) ◽

pp. 6797 ◽

Cited By ~ 40

Author(s):

Shai N. Shafrir ◽

Henry J. Romanofsky ◽

Michael Skarlinski ◽

Mimi Wang ◽

Chunlin Miao ◽

...

Keyword(s):

Carbonyl Iron ◽

Iron Particle ◽

Magnetorheological Fluid ◽

Optical Glasses ◽

Carbonyl Iron Particle

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Influence of Different Gradation Carbonyl Iron Particles on the Properties of Magneto-Rheological Fluids

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.452-453.623 ◽

2012 ◽

Vol 452-453 ◽

pp. 623-627

Author(s):

Cheng Bin Du ◽

Guo Jun Yu ◽

Zhi Wei Gong

Keyword(s):

Mechanical Properties ◽

Particle Size ◽

Shear Stress ◽

Single Particle ◽

Carbonyl Iron ◽

Iron Particle ◽

Iron Particles ◽

Carbonyl Iron Particle ◽

Magneto Rheological ◽

Multiple Particle

The influence of carbonyl iron particles sizes on the properties of magneto-rheological fluids (MRFs) were studied. Different-sized carbonyl iron magnetic particles were prepared by ball milling with different milling times. On this basis, different particle MRF were prepared The off-state viscosity and the shear stress of the above MRFs were characterised and studied by an advanced rotational rheometer system. The test results show that the off-state viscosity and the shear stress of single-particle MRFs were enhanced with increasing average carbonyl iron particle size at a constant magnetic field. The shear stresses of MRFs containing two or three different particle sizes were significantly improved compared with the MRFs containing only a single particle size. At a reasonable level of medium and small size carbonyl iron particle spread throughout the structure of the multiple-particle MRFs, the defects in the chain structure were remedied when a chain reaction occurred, and the mechanical properties of MRFs were enhanced. Meanwhile, increased mass fractions of the small size carbonyl iron particle resulted in a reduction in overall average particle size of MRFs, and the mechanical properties of MRFs were also reduced. The mechanical properties of multiple-particle MRFs were observed to be strongly dependent on the size and mass fraction of the medium and small carbonyl iron particles.

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