Composite Rolling Research Articles

Rolling of powder composites reinforced with mesh

Rolling of powder composites reinforced with mesh

Rolling of powder composites reinforced with mesh

Rolling of powder composites reinforced with mesh

Development of guide rollers using electroplated carbon fiber-epoxy composite for thin polymer film processing

Since thin polymer films can not sustain the large tension generated from the rotational inertia of a guide roller during start and stop periods of film processing and can be easily damaged by the rough surface of the guide roller, the guide roller should have low rotational inertia, low friction coefficient, high bending stiffness and fine surfaces. The carbon fiber-epoxy composite material electroplated with chromium has excellent properties for the structure of the guide roller due to its high specific modulus and high damping, which reduces induced vibrations. In this paper, the design and manufacturing methods as well as the static, dynamic and frictional characteristics of the carbon fiber-epoxy composite rollers electroplated with chromium were investigated using analytical and experimental methods to improve the performance of the high speed guide roller.

Deformation analysis of composites formed by powder plating and rolling

Composite rolling with metallic powders and metallic sheet is a new technology for producing composites. In this paper, samples of composites of Cu — steel, Al —steel, Sn — steel and Stainless steel — steel have been formed with this method. The relationships between the rolling force and the deformation of both the powders and the metal matrix have been studied. Some conclusions are drawn.

The characteristics of the deformation and flow process in the rolling of metal sheets and metal powders of composite materials

The rolling of metal sheets and metal powders of composite materials is anaasymmetric rolling process for the workpiece. The deformation of the rolled-piece, powder gains and the joining deformation of the composite interface are discussed and analyzed in this paper. Many experimental results are given for the deformation of the powder and the bending tendency of the rolled-piece. The characteristic of metallic deformation and flow process are discussed. Finally, some conclusions regarding the composite rolling process are given.

Metallic wear resistant coatings for carbon fibre epoxy composite rolls

Carbon fibre reinforced polymer rolls are an interesting alternative to steel or aluminium rolls for the paper, textile and foil industries on account of their great stiffness and very low inertia. However, their application is inpeded by insufficient wear resistance. In cooperation with a roll manufacturer, a technology was developed to apply a coating system of superior wear resistance to these rolls. The process consists of several steps: (1) microroughening of the substrate surface, (2) deposition of nucleation sites, (3) electroless deposition of an NiP coating, (4) chrome plating. The most critical area of this coating system is the interface polymer-NiP layer. Because the van der Waals bonds are too weak to give sufficient adhesive strength, the substrate surface has to be prepared very carefully for optimum mechanical interlocking by grit blasting. In this way an adhesive strength up to 20 MPa could be achieved, as measured by pull-off tests. This often exceeds the cohesive strength of the carbon fibre/epoxy composite. Apart from the process technology, the paper also adresses the characterization of the coatings with respect to microstructure, surface quality and wear resistance.

Development of High Performance New Composite Roll.

Development of High Performance New Composite Roll.

高性能圧延機用新複合ロール

高性能圧延機用新複合ロール

Fabrication of formable metal-metal composites

Composite fabrication techniques were developed for the reinforcement of a precipitation-hardening aluminium alloy (Duralumin) with stainless steel and maraging steel and for the reinforcement of titanium alloys with high strength steel using an in situ ausforming (hot-cold working) operation. Both sheet and rod composites were produced using roll-bonding and hot-pressing techniques. Maximum permissible levels of rolling deformation in the direction of reinforcement were determined for these composites during both their fabrication and the subsequent rolling sequences using the previously developed formability criteria. Owing to the large difference in flow strengths between the Duralumin and steel reinforcement under the conditions of fabrication and cold rolling there was an upper limit of deformation achievable in the Al-steel composites. No such limit was found on using continuous “hot-cold”-rolling techniques for Ti-steel composites between the steel austenitizing temperature and 400°C. However, cold rolling of the Ti-steel composites was not possible because of the large difference in flow strengths between the matrix and reinforcement and the poorly sustained work-hardening rate of the ausformed steel reinforcement. Nevertheless, Al-steel and Ti-steel composites were produced which are capable of competing with the high strength light metals in terms of their specific strength and, at the same time, are capable of undergoing a certain amount of rolling deformation in the direction of reinforcement alignment.

Constant-Deflection Rolls—A New Solution to an Old Problem

The problem of designing a set of rolls exerting a uniform pressure on material passing between them has elicited many different solutions, none quite satisfactory. A new solution, presented here, uses composite rolls having a cigar-shaped inner core and a cylindrical outer shell, the gap between them being filled with a soft elastomer containing approximately 15 percent air bubbles. The core profile is calculated according to equations derived here. The solution produces even roll pressure for any load, without the need for making adjustments to match changing loads. At the same time, the solution is mechanically very simple and reliable.

The Rolling and Annealing Characteristics of Molybdenum Fiber-reinforced Copper Composites through Internal Friction Measurements

The Rolling and Annealing Characteristics of Molybdenum Fiber-reinforced Copper Composites through Internal Friction Measurements

Elastohydrodynamic Lubrication of Roller Bearings

Abstract Roller bearing endurance tests have been run on groups of bearings with L10 and L50 lives established by Weibull analysis. Bearing roller path surface finish, shaft speed, lubricant viscosity and lubricant temperature were varied. Relevant tapered roller and cylindrical roller bearing life data was selected from prior tests for comparison. Weibull plots show the effect of the variables on life and a graph comparing the ratio of L10 test life to the calculated life and the ratio of elastohydrodynamic lubricant film thickness to composite rolling contact surface finish is given. An empirical equation to predict the effect of varying lubricant and surface finish conditions on fatigue life is given.