Method For Evaluation Of Adhesion Research Articles

Evaluation of interfacial shear strength by tensile tests of impregnated flax fiber yarns

Adhesion of flax fibers and polymer matrix as well as mutual bonding of elementary fibers in a technical fiber are among the principal factors governing the mechanical response of flax fiber-reinforced polymer–matrix composites. A method for evaluation of adhesion is proposed based on tension tests of impregnated fiber yarns, with subsequent characterization by optical microscopy of length distribution of fibers pulled out of the yarn fracture surfaces. An elementary probabilistic model is derived relating aspect ratio distribution of the pulled-out fibers to the fiber tensile strength distribution and the effective interfacial shear strength (IFSS). The method was applied to flax fiber/vinylester resin yarns and an estimate of IFSS at 17 MPa was obtained.

D11 切削抵抗動的成分による凝着性評価と工具摩耗(OS14 先端材料・難削材の加工(2))

D11 切削抵抗動的成分による凝着性評価と工具摩耗(OS14 先端材料・難削材の加工(2))

Evaluation of Adhesion on Tool-Chip Interface with Dynamic Components of Cutting Force

A new method for evaluation of adhesion in cutting is proposed. Adhesion of chip induces fluctuation in chip flow or stick-slip movement of chip, so that dynamic component of cutting forces depends on the cutting conditions and properties of the work materials. Continuous turning of a medium carbon steel, a titanium alloy and a nickel-based super heat resistant alloy were carried out. Dynamic components of cutting force were measured by piezoelectric dynamometer. In cutting of a medium carbon steel, the dynamic components below 500Hz increased under the condition of build-up edge (BUE) formation, and gradually decreased with increase of cutting speed. Deposits of work piece on tool face were also observed under conditions in which the power spectrum of cutting force showed peaks. Authors defined friction-coefficient vector on rake face of cutting tool. Fluctuation in the friction-coefficient vector was calculated as for a range of cutting speeds under dry condition and emulsion supply in order to investigate the relationship between adhesion and fluctuation of the dynamic components. Tendency to adhesion was evaluated with newly defined index among a carbon steel S45C, a titanium alloy Ti-6Al-4V and a nickel-based super heat resistant alloy Inconel718, yielded good agreement with empirical rules.

The Relationship between Dynamic Components of Cutting Force and Adhesion of Tool-Chip Interface

A new method for evaluation of adhesion in cutting is proposed. Adhesion of chip induces fluctuation in chip flow or stick-slip movement of chip, so that dynamic component of cutting forces depends on the cutting conditions and properties of the work materials. In this investigation continuous turning of a medium carbon steel was carried out and dynamic components of cutting forces are measured by piezoelectric dynamometer. Fluctuation in dynamic force on rake face of the tool is considered at a range of cutting speeds under dry condition and oil-mist lubrication. Surface profiles of machined surfaces and sticking of chip on tool face were also investigated. In cutting of medium carbon steel, the dynamic components below 500Hz increased under the condition of build-up edge (BUE) formation, and gradually decreased as increase of cutting speed. Tool-edge geometry well transferred onto the machined surface when the dynamic components were low level. Smoothness of chip flow on rake face is strongly associated with good surface finish.

The Relationship between Dynamic Components of Cutting Force and Adhesion of Tool-Chip Interface

A new method for evaluation of adhesion in cutting is proposed. Adhesion of chip induces fluctuation in chip flow or stick-slip movement of chip, so that dynamic component of cutting forces depends on the cutting conditions and properties of the work materials. In this investigation continuous turning of a medium carbon steel was carried out and dynamic components of cutting forces are measured by piezoelectric dynamometer. Fluctuation in dynamic force on rake face of the tool is considered at a range of cutting speeds under dry condition and oil-mist lubrication. Surface profiles of machined surfaces and sticking of chip on tool face were also investigated. In cutting of medium carbon steel, the dynamic components below 500Hz increased under the condition of build-up edge (BUE) formation, and gradually decreased as increase of cutting speed. Tool-edge geometry well transferred onto the machined surface when the dynamic components were low level. Smoothness of chip flow on rake face is strongly associated with good surface finish.

Evaluation of adhesion between coating and substrate by a single pendulum impact scratch test

The Single Pendulum Impact Scratch Test (SPIST) with high precision for measuring impact energy consumption during scratching has been developed. A new criterion for evaluating adhesion between coating and substrate has been suggested. Some super hard coating (TiN) deposited by physical vapor deposition and rather tough coating (Ni–P) prepared by electroless plating have been tested. The SPIST result of adhesion of TiN coating/substrate shows a good correspondence with that in the Acoustic Emission Monitoring Scratch Test (AEMST). The physical meaning of energy criterion from SPIST is more distinctive than that of the critical load from AEMST. The difficulty of weak or absent acoustic emission signal during the steady scratch test for evaluation of adhesion of tough coating/substrate could be overcome by SPIST and its result of Ni–P/1045 steel is also in consistence with that of Direct Pull-off test — a common method for evaluation of adhesion of plating or painting.