Matte Surface Research Articles

Design aspects involved in a cemented THA stem failure case

Fatigue failure of total hip arthroplasty stem is today a rare case due to improvements of the technique along many decades. However, any case of stem fracture should be treated with attention due to the problems that can result in the revision for the patient. The most common cause of stem fracture is the proximal aseptic loosening. This scenario is reproduced in endurance test protocol ISO 7206-4 and should be applied for all design changes to prevent fracture of the stem even in the event of mechanical or biological problem that result in the aseptic loosening. This paper presents a cemented hip stem failure analysis. The study consisted of fracture analysis, material characterization, numerical simulation of the stem under the conditions of the endurance test, as well as fatigue tests of the ASTM F 745 stainless steel. The failure, in the mechanical aspect, is associated to the use of the cast stainless steel and could have been predicted through testing prior commercialization. Some design aspects are discussed. The use of cylindrical distal portion, matt surface and collar can reduce the stability in a loosened cemented hip stem.

Failure analysis of contact probe pins for SnPb and Sn applications

A study has been conducted to investigate the failure mechanism of pogo pin-type probe contacts. Probe pins are used for electrical test of microelectronic components in manufacturing. A false rejection of parts due to high probe contact resistance results in a penalty in cost and yield. The probe pin contact bears distinctive characteristics of failure compared to the conventional contact systems such as mechanical switches and interconnects. Moreover, the transition to Pb-free component leads demands understanding of different probe failure mechanisms between a SnPb and Sn surface. The objective of this study is to understand this unique failure mechanism and the effect of lead coating metals on probe pin life. This has not been clearly elucidated to date in spite of its significant impact on yield and cost of electronic package manufacturing. A simulated probe tester with 3-axes actuation capability was devised to mimic the actual test process. The force required to penetrate the surface oxide layer and develop electrical contact was measured. Contact resistance history revealed that probe pins mating to Sn surfaces failed earlier than pins used on SnPb surfaces. Through periodic inspection of probe pins using microprobe/EDS as a function of probe actuations, the general root cause of probe pin failure was found to be probe pin tip wear out associated with the Sn oxide growth on its surface. The matte Sn surface wears the probe pin more than SnPb due to the rough and abrasive nature of the matte Sn surface.

P‐44: Overall Judgment by Comparison with Polish and Matt Surface for some FPDs with Analytic Hierarchy Process

AbstractWe evaluated the priority order among four image quality factors:legibility/readability, sharpness/pureness, graleness/fatigue and reality/fidelity, and compared the image qualities to four surface treatments: polish, polish with anti‐reflection treatment and matt surfaces as 12% and 25% haze, for three applications with main size panels: mobile‐phone, PC, television by using analytic hierarchy process.

投影面の反射特性とハイライト除去を考慮した複数プロジェクタによる重畳投影

Visitors cannot always view objects displayed in the cases in most museums as well as desired because of light reflecting from the glass. Not only their fade color but also highlights of the glass in the showcases make studying them in detail difficult. We present an overlapped multi-projection display system for creating a high-color appearance onto the surface of an object. Our system can also be used to compensate for the distortion caused by the reflection. Such as system is suitable for compensating for the distortion caused by the maximum color and brightness of images presented with conventional projectors. To reduce the loss of quality caused by the highlights, each projector automatically excludes the specular direction area, and then another projector complements the exclusion. Using this combined approach expands the range of the colors that can be reproduced and reduces the detrimental effect of the brighter area. We introduce overlapped multi-projection and show experimental results for when the appearance of the color of regular gradation patterns was changed and the appearance of a painting that had naturally degraded. Our method can be applied to all types of projection onto screens that do not have a matt surface.

Testing limits on matte surface color perception in three-dimensional scenes with complex light fields

We investigated limits on the human visual system’s ability to discount directional variation in complex lights field when estimating Lambertian surface color. Directional variation in the light field was represented in the frequency domain using spherical harmonics. The bidirectional reflectance distribution function of a Lambertian surface acts as a low-pass filter on directional variation in the light field. Consequently, the visual system needs to discount only the low-pass component of the incident light corresponding to the first nine terms of a spherical harmonics expansion [Basri, R., Jacobs, D. (2001). Lambertian reflectance and linear subspaces. In: International Conference on Computer Vision II, pp. 383–390; Ramamoorthi, R., Hanrahan, P., (2001). An efficient representation for irradiance environment maps. SIGGRAPH 01. New York: ACM Press, pp. 497–500] to accurately estimate surface color. We test experimentally whether the visual system discounts directional variation in the light field up to this physical limit. Our results are consistent with the claim that the visual system can compensate for all of the complexity in the light field that affects the appearance of Lambertian surfaces.

The electrochemical polishing behavior of the Inconel 718 alloy in perchloric–acetic mixed acids

The electropolishing behavior of the Inconel 718 alloy was studied by using rotating disc electrode (RDE) in the HClO 4–CH 3COOH mixed acids with different HClO 4-concentrations. After electropolishing, surface morphologies of RDE specimens were examined with surface profiler, atomic force microscope and scanning electron microscope. According to the surface morphologies observed, three types of anodic dissolution behavior can be characterized in relation to the HClO 4-content in mixed acids; namely, leveling without brightening of the surface in the mixed acids with 10 and 20 vol% HClO 4, leveling and brightening of the surface in the mixed acids with 30 and 40 vol% HClO 4, and a matt and gray surface in the mixed acids with 50 vol% or more HClO 4. Anodic dissolution in the first and second dissolution types follows a mass-transfer controlled mechanism, in which a linear relationship between the reciprocal of limiting-current density and the reciprocal of square root of rotating speed of RDE specimen can be detected. Owing to precipitation of salt film on the polished surface of the Inconel 718 material, saturated dissolved metallic ions could be the chemical species for the mass-controlled mechanism. The salt film, in addition, could enhance the corrosion resistance of the Inconel 718 alloy.

Exeter total hip arthroplasty with matte or polished stems

To compare implant survival rates after total hip arthroplasty with Exeter matte or polished stems and to determine the relationship of synovitis/joint effusion to signs of implant loosening and stem type. The first part of the study included retrospective revision rate analysis of 118 primary hip replacements performed during 1991-1995. Two different designs of Exeter stems were used: matte surface stems during 1991-1995 (matte surface group--47 cases), and polished stems during 1992-1995 (polished stem group--71 cases). During the second part of the study, 24 patients (11 in polished stem group and 13 in matte stem group) were prospectively examined with radiography and sonography. Sonography was performed in order to evaluate capsular distension, i.e. the distance between prosthetic femoral neck and anterior capsule. Capsular distension depends on synovitis and/or synovia in prosthetic hip. The relationship between capsular distension, stem type, and radiographic signs of loosening was assessed. For the first part of our study, total implant survival was 78% with matte stems and 61% with polished stems 13 years postoperatively (P=0.27). Stem survival was 82% for matte stems, and 88% for polished stems (P=0.54). In the second part of study, a significant relationship between increased capsular distension and cup loosening was determined (P=0.04). We did not find significant difference in capsular distension when compared matte and polished stems. Implant survival rates did not differ between the groups. The relationship between capsular distension and cup loosening was statistically significant.

Photo-Quality Print Media

This paper will describe a photo-quality print media comprising a specially developed image-receiving surface layer (IRL) that accepts the printing ink/colorant material from the appropriate printing process, and serves to embed it in the glossing step, providing for better image protection and better image properties without additional coatings or a lamination step. The IRL is extrusion coated as an extruded monolayer or coextruded along with other layers to both sides of the base. The backside of the media can be tailored for specific applications (writability before and after printing, fuser oil management in electrophotographic applications, etc.).A unique advantage of the IRL is the fact that its final surface finish can easily be altered for specific applications. This media can provide a matte surface for printing directed to specified applications. Alternatively, the same material can be glossed to an even gloss finish by passing the printed media through a glossing unit, such as a belt fuser, to yield a highly glossed printed surface without additional coatings. Such versatility, an unprecedented and unobvious technical advance in the world of printed media, is a unique economic advantage offered by the media described here.

Total Hip Arthroplasty with a Cemented, Polished, Collared Femoral Stem and a Cementless Acetabular Component

Recent studies have suggested that cemented femoral components with a polished surface may provide superior long-term fixation when compared with femoral components with a roughened surface. The purpose of this study was to evaluate the results of total hip arthroplasty with a cemented femoral component with a polished surface finish and compare them with the results of total hip arthroplasty performed with a similar design of cemented femoral component with a rougher surface finish. We retrospectively reviewed a consecutive group of 132 patients (149 hips) in whom primary total hip arthroplasty had been performed by one surgeon using a cemented collared femoral component with a polished (0.1-microm Ra) surface finish and a cementless acetabular component. Ninety-eight patients (115 hips) were followed for a minimum of ten years. We compared the survivorship of this prosthesis with that of a femoral component of similar design but with rougher surfaces (matte or grit-blasted). No polished stems were revised because of aseptic loosening or demonstrated radiographic evidence of loosening; however, eight hips (5.4%) with a polished stem demonstrated osteolysis distal to the greater or lesser tro-chanter. In contrast, six stems (2.0%) with a matte surface finish of 0.8-microm Ra were revised because of aseptic loosening, and an additional five stems were seen to be loose radiographically. Eleven stems (9.2%) with a grit-blasted surface finish of 2.1-microm Ra were revised because of aseptic loosening, and an additional four stems were seen to be loose radiographically. The difference in the prevalence of revision due to aseptic loosening between the group with the 0.1-microm Ra surface and the group with the 2.1-microm Ra surface was significant (p = 0.001), as was the difference between the prevalence of revision due to aseptic loosening between the group with the 0.8-microm Ra surface and the group with the 2.1-microm Ra surface (p = 0.001). No cups were revised because of aseptic loosening, and one hip had radiographic signs of acetabular loosening. This study demonstrated excellent durability of a prosthesis consisting of a cemented, collared, polished femoral component and a cementless acetabular component. While no hips were revised because of aseptic loosening, distal femoral osteolysis was observed in eight hips (5.4%), a higher prevalence than has been reported by others after similar durations of follow-up of tapered, collarless, polished femoral components.

Total Hip Arthroplasty with a Cemented, Polished, Collared Femoral Stem and a Cementless Acetabular Component

Background: Recent studies have suggested that cemented femoral components with a polished surface may provide superior long-term fixation when compared with femoral components with a roughened surface. The purpose of this study was to evaluate the results of total hip arthroplasty with a cemented femoral component with a polished surface finish and compare them with the results of total hip arthroplasty performed with a similar design of cemented femoral component with a rougher surface finish. Methods: We retrospectively reviewed a consecutive group of 132 patients (149 hips) in whom primary total hip arthroplasty had been performed by one surgeon using a cemented collared femoral component with a polished (0.1-μm Ra) surface finish and a cementless acetabular component. Ninety-eight patients (115 hips) were followed for a minimum of ten years. We compared the survivorship of this prosthesis with that of a femoral component of similar design but with rougher surfaces (matte or grit-blasted). Results: No polished stems were revised because of aseptic loosening or demonstrated radiographic evidence of loosening; however, eight hips (5.4%) with a polished stem demonstrated osteolysis distal to the greater or lesser tro-chanter. In contrast, six stems (2.0%) with a matte surface finish of 0.8-μm Ra were revised because of aseptic loosening, and an additional five stems were seen to be loose radiographically. Eleven stems (9.2%) with a grit-blasted surface finish of 2.1-μm Ra were revised because of aseptic loosening, and an additional four stems were seen to be loose radiographically. The difference in the prevalence of revision due to aseptic loosening between the group with the 0.1-μm Ra surface and the group with the 2.1-μm Ra surface was significant (p = 0.001), as was the difference between the prevalence of revision due to aseptic loosening between the group with the 0.8-μm Ra surface and the group with the 2.1-μm Ra surface (p = 0.001). No cups were revised because of aseptic loosening, and one hip had radiographic signs of acetabular loosening. Conclusions: This study demonstrated excellent durability of a prosthesis consisting of a cemented, collared, polished femoral component and a cementless acetabular component. While no hips were revised because of aseptic loosening, distal femoral osteolysis was observed in eight hips (5.4%), a higher prevalence than has been reported by others after similar durations of follow-up of tapered, collarless, polished femoral components. Level of Evidence: Therapeutic Level III. See Instructions to Authors for a complete description of levels of evidence.

Experimental investigation of roughening of the matt surface in pack rolling

Pack rolling, wherein two stacked sheets of material are rolled at the same time, is widely used in the final pass during manufacture of aluminium foil. The resultant foil has a bright surface from the contact with the rolls and a matt surface at the interface between the two sheets. For this laboratory study, cold-rolled aluminium sheets, both with and without annealing, were subjected to pack rolling. The stacked sheets were reduced by 50% in thickness. Lubrication on the interface was varied. It is found that annealing before pack rolling leads to a significantly rougher matt surface. Lubrication on the interface does not have a strong effect on the roughening. It is also found that the topographies of the upper and lower interfaces after pack rolling are practically coincident.

Surface color perception in three-dimensional scenes

Researchers studying surface color perception have typically used stimuli that consist of a small number of matte patches (real or simulated) embedded in a plane perpendicular to the line of sight (a "Mondrian," Land & McCann, 1971). Reliable estimation of the color of a matte surface is a difficult if not impossible computational problem in such limited scenes (Maloney, 1999). In more realistic, three-dimensional scenes the difficulty of the problem increases, in part, because the effective illumination incident on the surface (the light field) now depends on surface orientation and location. We review recent work in multiple laboratories that examines (1) the degree to which the human visual system discounts the light field in judging matte surface lightness and color and (2) what illuminant cues the visual system uses in estimating the flow of light in a scene.

Ten-Year Survivorship of Rough-Surfaced Femoral Stem With Geometry Similar to Charnley Femoral Stem

The aim of this study is to review the 10-year results of 269 cemented total hip arthroplasties performed using the Harvard femoral stem with matte surface finish and Charnley stem-like geometry. This is a retrospective cross-sectional survivorship study. We retrospectively reviewed the results of 269 cemented total hip arthroplasties performed using the Harvard femoral stem in 257 patients (men/women 93:164, mean age 71.2 years) between 1990 and 1994. The median duration of follow-up for the surviving implants was 118 (range 60-129) months. Radiographs were reviewed to evaluate the type of osteoarthritis, cement mantle thickness, alignment of the components, presence of aseptic loosening, and radiolucent lines. Kaplan-Meier survival analysis and Cox proportional hazards analysis were performed to evaluate 10-year survival and the impact of various radiological parameters on the prosthesis survival respectively. Of the 248 eligible patients (260 hips), 6 patients (7 hips) were lost to follow-up, and 67 patients had died at the time of the study; 36 hips (35 patients) underwent revision surgery for aseptic failure (median duration 60 months, range 12-125 months), and 11 hips were revised for septic failure (median duration 24 months, range 10-53 months from the index procedure). The femoral component was revised in all patients, whereas the acetabular component was revised in 27 patients. Ten-year survival for the femoral and acetabular components using aseptic loosening (with and without revision surgery) as an end point was 77.5% (71.5%-83.5%) and 91.1% (87.2%-95%), respectively. Cox regression analysis did not reveal a statistically significant ( P > 0.05) effect of various radiological parameters on survival rate. Our results demonstrate that the matte surface finish femoral component (with geometry similar to Charnley femoral component) has less satisfactory long-term survival rate.

A comparative FEA of the debonding process in different concepts of cemented hip implants

Debonding of the stem–cement interface and damage accumulation in the cement mantle are basic events that contribute to the long-term failure of cemented hip reconstructions. In this work, a numerical study with these two processes coupled is presented. On the one hand, debonding of the stem–cement interface was simulated by means of a cohesive surface theory that was implemented into an interface finite element. This interface model includes a tensile-shear behavior law, the fatigue failure of the interface, and the friction evolution between both surfaces. On the other hand, damage accumulation in the cement was formulated through the theory of continuum damage mechanics, considering cement damage due to tension, creep under compression, crack closure effects, non-linear damage accumulation and cement residual stresses appearing during polymerisation. This methodology was applied to simulate and compare the degradation process of the cement and stem–cement interface in four different concepts of design: Exeter, Charnley, Elite Plus and ABG II stems. As the actual mechanical properties of the surface of each specific prosthesis are not known, we assumed the same for all of them, distinguishing between polished and matt surfaces. With this assumption, the predicted results showed that the debonding process is very different for each implant depending on the stem geometry. Lower cement deterioration was obtained for the Exeter and ABG II stems, while the lowest stem–cement interface debonding was produced in the Exeter and the Elite Plus stems.

Chemical resistance and cleanability of glazed surfaces

Adhesion of soil on glazed surfaces and their cleanability depends on chemical composition, phase composition, and roughness of the surface. The surface can be glossy consisting mainly of a smooth glassy phase. A matt and rough surface consists of a glassy phase and one or more crystalline phases. The origin and composition of the crystalline phases affect the chemical resistance and the cleanability of the surface. Fifteen experimental glossy and matt glazes were soaked in a slightly alkaline cleaning agent solution. The surfaces were spin-coated with sebum, i.e. a soil component typical for sanitary facilities. After wiping out the soil film in a controlled manner, the surface conditions and the soil left were evaluated with colour measurements, SEM/EDXA and COM. The results show that wollastonite-type crystals in the glaze surfaces were attacked in aqueous solutions containing typical cleaning agents. This corrosion led to significant decrease in the cleanability of the surface. The other crystal types observed, i.e. diopside and quartz crystals were not corroded, and the cleanability of glazes containing only these crystals was not changed in the cleaning agent exposures. Also the glassy phase was found to be attacked in some formulations leading to a somewhat decreased cleanability. The repeated soiling and cleaning procedures indicated that soil is accumulated on rough surfaces and surfaces which were clearly corroded by the cleaning agent.

Analysis of 16 Retrieved Proximally Cemented Femoral Stems

Sixteen proximally cemented, collared, and distally splined, Bridge Hip femoral stems with a matte proximal surface and smooth distal surface were retrieved because of loosening. Electron microscopy, with correlated elemental analysis, identified titanium particulate embedded in the internal surface of the cement mantle. Data supported the observations that loosening of the femoral stems was related to proximal debonding at the cement-implant interface, loosening at the proximal cement-bone interface, and inherent rotational instability. Cement-implant interface debonding resulted in the proximally matte femoral stem surface abrading with the opposing cement mantle, resulting in particulate and osteolysis in some cases. Careful consideration of implant design and clinically relevant biomechanical testing protocols should be considered before the clinical introduction of future proximally cemented femoral stems.

Staged bilateral total hip arthroplasty using rough and smooth surface femoral stems with similar design: 10-year survivorship of 48 cases

Background Various studies have reported good long-term results using femoral stems with either smooth or rough surfaces. In this retrospective cross-sectional survivorship study, we reviewed the 10-year results of 51 bilateral staged cemented total hip arthroplasties using the Harvard or the Charnley femoral stems—which have almost similar geometry but a different surface finish.Methods 51 patients were reviewed at median interval of 10 (Harvard group) and 11 years (Charnley group) after the primary operation. We evaluated cement mantle thickness, alignment of the components, presence of radiolucent lines, and aseptic loosening. Kaplan-Meier analysis was performed to calculate the survival rate using various endpoints.Results 8 hips in the Harvard group were revised for aseptic loosening of thefemoral component at a median interval of 6.3 years after the primary procedure. 3 hips in the Charnley group were revised for aseptic loosening of the femoral and acetabular components between 10 and 11 years after the primary procedure. The 10-year survival rate for the femoral component using revision surgery for aseptic loosening as an endpoint was 80% (95% CI: 31–42) and 95% (95% CI: 44–47) in the Harvard and the Charnley group, respectively. Cox regression analysis did not reveal any statistically significant effect of various radiographical parameters on the survival rate (p < 0.05).Interpretation Our results demonstrate that in the group of patients studied, the femoral stem component with the matt surface finish had less satisfactory 10-year survival than the femoral stem of similar design which had a smooth surface finish. ▪

Influence of friction on roughening of the matt surface in aluminium pack rolling

A model has recently been presented to simulate inhomogeneous deformation of polycrystalline materials. This model was based on a finite element analysis using an isotropic plasticity model for the material with a distribution of strengths to simulate the crystallographic texture. By considering plane-strain compression of monolithic material, the displacements generated at the midplane successfully provided a prediction of the roughness at the interface of pack-rolled aluminium foil. In the current study, the predictions of the model are explored further. First, the influence of the friction coefficient μ at the interface between the sheets is assessed using a plane-strain compression model of two sheets. It is found that roughness does not depend greatly on μ when μ>0.1, being close to that predicted by the monolithic model. However, the roughness does increases significantly as μ falls below 0.1. Secondly, a plane-strain rolling model is used to clarify the effects of friction between the roll and the strip. It is found that neither the friction at the roll surface nor the roll diameter has a strong effect on the roughening of the internal matt surface. It is concluded that the model using plane-strain compression of monolithic material is appropriate to predict the roughness on the matt surface of pack-rolled materials.

Evolution of matt surface topography in aluminium pack rolling. Part I: model development

Roughening of the matt surface of pack rolled aluminium foil has been modelled. The model is based on the finite element method using isotropic plasticity. A distribution in material properties has been used to simulate the distribution of grain orientations through the material. It is found that the formation of shear bands causes roughening of the matt surface. The length of these shear bands allows individual grains or the hard roll to influence the roughness a significant distance away. Results show the effect of the ratio of the grain size to the strip thickness on the predicted roughness generated. The predictions show good qualitative agreement with the reported experiments. It is concluded that the model is able to simulate efficiently the effect of the granular behaviour of polycrystals on the matt surface roughness.

Evolution of matt surface topography in aluminium pack rolling. Part II: effect of material properties

A model has been presented in a companion paper [1] to predict the generation of roughness on the matt surface in pack rolling of aluminium foil. The model is based on the finite element method using isotropic plasticity. This model is used in the current paper to investigate the effect of material properties on the generation of surface roughness. There is a large inhomogeneity of strain during deformation, with harder grains generally deforming less than softer ones. It is found that the roughness amplitude is roughly proportional to the standard deviation of the initial grain yield stress distribution, normalised by the initial mean yield stress, so that a wider distribution of the initial yield stress results in greater surface roughness. It is shown that a suitable linear hardening law can be used to approximate the roughening behaviour for real material flow stress curves.