Investigation of Residual Stresses in Flame Sprayed Ni-Based Wear Resistant Coatings by the Hole-Drilling and X-Ray Methods

2013 ◽  
Vol 768-769 ◽  
pp. 144-149 ◽  
Author(s):  
Alexander Ryabchikov ◽  
Harri Lille ◽  
Renno Reitsnik ◽  
Stanislav Toropov ◽  
Andrei Surženkov ◽  
...  

The present investigation was carried out in order to determine residual stresses inNi-based self-fluxing alloy based high velocity oxy-fuel (HVOF) coatings with different wearresistant additives. The main components of the alloy were Ni, Cr, Si and B. To increase the wearresistance of self-fluxing NiCrSiB alloy based coatings, different ceramics and hard metals(WC-Co, TiC-NiMo and Cr2C3-Ni) were added. Residual stresses were measured by the holedrillingmethod and the X-ray method. The incremental hole-drilling technique combined with theintegral method was applied. This combined method allows to analyse non-uniform throughthicknessresidual stresses. The results obtained with the incremental hole-drilling method indicatethat through-thickness residual stress distribution is non-uniform. The determined residual stresseswere tensile on the surface of the coating and became compressive toward the interface.The values of the modulus of elasticity and microhardness of the coatings were obtained byinstrumented indentation. The microstructures of the studied coatings were investigated with theSEM technique.

2014 ◽  
Vol 996 ◽  
pp. 445-450 ◽  
Author(s):  
Wulf Pfeiffer ◽  
Eduard Reisacher ◽  
Michael Windisch ◽  
Markus Kahnert

Friction stir welding (FSW) is a well-known technique which allows joining of metal parts without severe distortion. Because FSW involves less heat input relative to conventional welding, it may be assumed that cutting specimens from larger friction stir welded components results in a negligible redistribution of residual stresses. The aim of the investigations was to verify these assumptions for a welded aluminum plate and a circumferentially-welded aluminum cylinder. Strain gage measurements, X-ray diffraction and the incremental hole drilling method were used.


2013 ◽  
Vol 768-769 ◽  
pp. 464-469
Author(s):  
Maria José Marques ◽  
António Castanhola Batista ◽  
Luís Coelho ◽  
Joao P. Nobre ◽  
Altino Loureiro

The samples studied in this paper were performed from carbon steel plates, cladded in one of the faces with stainless steel filler metals by submerged arc welding (SAW). After cladding work, the samples were submitted to post-weld heat treatments at different conditions and afterwards stainless steel coating surfaces were milled and mechanically polished, as in the industrial application. The residual stress analysis was performed by X-ray diffraction (XRD) and incremental hole-drilling methods (IHDM). The residual stresses profiles presented different in depth values in each sample, depending on the heat treatment conditions. The hole-drilling method was applied in several points of each stainless steel sample surface and the results presented similar evolution profiles. However compressive stresses increase with the increase of heat treatment temperature.


2014 ◽  
Vol 996 ◽  
pp. 958-963
Author(s):  
Zhong Meng Wen ◽  
Xiao Lu Gong

In this work, the residual stresses for composite laminates [02/θ2]S determined by means of the incremental hole-drilling method with a formula to express the relationship between the residual stresses and the relaxed strains around the drilled hole. Then the ageing tests related to hydrothermal condition are carried out to analyze the influence on the residual stress redistributions and also on the mechanical behaviors of the carbon/epoxy laminates.


1998 ◽  
Vol 65 (4) ◽  
pp. 837-843 ◽  
Author(s):  
Zhu Wu ◽  
Jian Lu ◽  
Bongtae Han

A new method combining Moire´ interferometry and the incremental hole-drilling method is developed to determine both uniform and nonuniform residual stress distribution in depth. The study is reported in two parts. In this first part, the theoretical development of the moire´ interferometry hole-drilling method is presented. The relationship between the in-plane surface displacements produced by introducing a blind hole and the corresponding residual stresses is established by employing the existing theoretical solution containing a set of undetermined coefficients. The coefficients are calibrated by the three-dimensional finite element method and they are processed nondimensionally for general use. The whole field in-plane surface displacements data Ux and Uy produced by the relaxation of residual stresses are obtained from moire´ interferometry after each increment of hole drilling. The high signal-to-noise ratio provided by moire´ interferometry allows accurate determination of fringe orders near the hole boundary which is essential for enhancing fidelity of residual stress determination. The experimental procedure to determine the signs of residual stresses is described and the accuracy of the method is also discussed.


2014 ◽  
Vol 996 ◽  
pp. 262-268
Author(s):  
Frank Schweizer ◽  
Marius Dickele ◽  
Michael Luke

The incremental hole-drilling method was adapted for the measurement of residual stresses in polymer based composite materials. The parameters of the hole drilling process and the strain measurement in non-reinforced and 70 weight-percent glass-fiber-reinforced polypropylene were investigated. Calibration coefficients for the calculation of the residual stresses in the orthotropic material systems were determined by Finite Element Analysis. By means of application of the method to unidirectional and cross-ply glass-fiber reinforced composites the residual stresses, maximum measurable depths and measurement uncertainties could be derived.


2015 ◽  
Vol 784 ◽  
pp. 361-368
Author(s):  
Zhong Meng Wen ◽  
Xiao Lu Gong

This work investigates the effect of residual stresses on the damage of composite laminate. The incremental hole-drilling method is applied to determine residual stresses in composite laminates [02/θ2]s and then acoustic emission technique is used for the identification of damage appearance during the tensile testing. The samples with different residual stress distribution are prepared through curing and post curing in order to study the role of residual stress on the damage of composite laminates. Besides the experimental method, the theoretical approach is applied to illustrate the role of residual stress on the damage of composite laminates.


2020 ◽  
Vol 4 (3) ◽  
pp. 143
Author(s):  
Tao Wu ◽  
Steffen R. Tinkloh ◽  
Thomas Tröster ◽  
Wolfgang Zinn ◽  
Thomas Niendorf

Lightweight materials contribute to an efficient decrease in fuel consumption in the automotive and aircraft industries. Hybrid components made of metal and carbon fiber-reinforced plastics (CFRP) have a high potential in lightweight applications due to their high strength-to-weight ratio. For cost-effective processing of hybrid materials, advanced manufacturing processes such as the prepreg-press-technology have been developed, in which the bonding between a metallic component and a fiber compound is exclusively realized in the forming process. However, upon processing of these hybrid components at elevated temperature, the difference in thermal expansion coefficients of the two materials leads to the formation of tensile residual stresses upon cooling. It is well known that these tensile residual stresses can be detrimentally effective with respect to the durability of a hybrid component. The objective of this work is to accurately measure and analyze residual stresses in hybrid components made of unidirectional CFRP and steel through the incremental hole drilling method. Within this study, the evaluation formalism for orthotropic materials is employed for measuring non-uniform residual stresses in hybrid materials. In order to improve the measurement accuracy, a customized strain gauge with eight grids is employed and a drilling increment size of only 20 µm is utilized. The influence of the angle between the strain gauge rosette and the fiber direction on the evaluation of the residual stresses is investigated. In order to evaluate the reliability of the results determined, a bending test applying a well-defined load is carried out. By direct comparison of the experimentally determined stresses and stress values calculated by the finite element method, the applicability of the hole drilling method for robust determination of residual stresses in CFRP/metal hybrid components is finally validated.


Sign in / Sign up

Export Citation Format

Share Document