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Viewing 1 to 30 of 4670
2017-10-13
Technical Paper
2017-01-5012
Harveer Singh Pali, Shashi Prakash Dwivedi
Abstract The present work deals with the fabrication and tribological testing of an aluminium/SiC composite. Fabrication was done using two techniques; mechanical stir casting and electromagnetic stir casting. Metal matrix composite (MMC) was fabricated using aluminium as a matrix and SiC as reinforcement in varying weight percentages. The wear and frictional properties of the MMC were studied by performing dry sliding wear test using a pin-on-disc wear tester for both types of samples. Wear rate retards with the increase the percentage of reinforcement whereas it improves with the addition of normal force. At same time frictional coefficient upsurges by increasing the normal force and percentage of reinforcement. Increasing percentage of reinforcement and using electromagnetic stir casting process obtained the higher frictional coefficient and lower wear rate.
2017-10-08
Technical Paper
2017-01-2379
Qian Feng, Shu Shen, Mengliang Li, Zhijun Li, Kongjian Qin, Diming Lou, Jiguang Wang, Xiyu Fang
Abstract Recent toxicological and epidemiologic studies have shown that diesel emissions have been a significant toxic air contaminant. Catalyzed DPF (CDPF) not only significantly reduces the PM mass emissions (>90%), but also further promotes carrier self-regeneration and oxidize more harmful gaseous pollutants by the catalyst coated on the carrier. However, some ultrafine particles and potentially harmful gaseous pollutants, such as VOCs species, originally emitted in the vapor-phase at high plume temperature, may penetrate through the CDPF filter. Furthermore, the components and content of catalyst coated on the CDPF could influence the physicochemical properties and toxicity intensity of those escaping ultrafine particles and gaseous pollutants. In this work, (1) we investigated the influence of precious metal content as a variable parameter on the physicochemical properties and catalytic activities of the small CDPF samples.
2017-09-30
Technical Paper
2017-01-5009
Li Fang, Henry Hu, Xueyuan Nie, Jimi Tjong, Xuezhi Zhang
Abstract In the present study, a design of experiment (DOE) technique, the Taguchi method, was used to develop as-cast high strength aluminum alloys with element additions of Si, Cu, Ni and Sr. The Taguchi method uses a special design of orthogonal arrays to study all the designed factors with a minimum of experiments at a relatively low cost. The element factors chosen for this study were Si, Cu, Ni and Sr content in the designed aluminum-based alloys. For each factor, three different levels of weight percentages were selected (Si: 6, 9, 12%, Cu: 3, 5, 7%, Ni: 0.5, 1, 1.5% and Sr: 0.01, 0.02, 0.03%). Tensile properties such as ultimate tensile strength, yield strength and elongation at failure were selected as three individual responses to evaluate the engineering performance of the designed alloys. The results of the factor response analysis were used to derive the optimal level combinations.
2017-09-22
Technical Paper
2017-01-5010
H.J. Liu, X.D. Zhang
Abstract In order to research the effect of process parameters (laser power, welding speed, wire-feed speed, spot diameter) on mechanical properties of Zn-coated Steel Laser Brazing Lap Joint for vehicle, the influence of welding parameters on energy input of brazing seam cross section was theoretically analyzed, and then a great number of laser brazing experiments of 0.7mm galvanized steel was carried out. After that, the tensile strength and micro-hardness tests were also done for well-formed joints of galvanized steel formed in the laser brazing. The results show that joints with good mechanical properties and surface morphology can be formed when laser power is in the range of 2500-3200W and the other parameters keep in a specified range. Joint performance significantly reduces when the value of wire-feed speed exceeds 3.0m/min for that a wider brazing seam cross section can’t be formed.
2017-09-19
Technical Paper
2017-01-2148
Ho-Sung Lee
In this paper, manufacturing of launcher structural components with superplastic forming (SPF) and solid state welding technologies is presented with several examples. Some of high strength aerospace alloys, like aluminum, titanium and superalloys, are known to have superplasticity so that complex shapes of aerospace components can be produced with this technology. A combination of superplastic forming and solid state welding processes produces lighter and stiffer components than one manufactured with conventional machining and welding. Solid state welding is an attractive method to weld materials without melting where mechanical properties are important since the welding interface is homogeneous without liquid phases.
2017-09-17
Journal Article
2017-01-2481
Vishal Mahale, Jayashree Bijwe, Sujeet Sinha
Abstract Potassium titanate (KT) fibers/whiskers are used as a functional filler for partial replacement of asbestos in NAO friction materials (FMs). Based on little information reported in open literature; its exact role is not well defined since some papers claim it as the booster for resistance to fade (FR), or wear (WR) and sometimes as damper for friction fluctuations. Interestingly, KT fibers and whiskers (but not powder) are proved as carcinogens by the International Agency for Research on Cancer (IARC). However, hardly any efforts are reported on exploration of influence of KT powder and its optimum amount in NAO FMs (realistic composites) in the literature. Hence a series of five realistic multi-ingredient compositions in the form of brake-pads with similar parent composition but varying in the content of KT powder from 0 to 15 wt% (in the steps of 3) were developed. These composites were characterized for physical, mechanical, chemical and tribological performance.
2017-09-17
Technical Paper
2017-01-2507
Matthias Hoch, Michal Kaczmarek, Markus Ahr
Abstract The demand for zinc-nickel coatings continuously increases in the automotive industry due to their high corrosion protection as well as superior wear and heat resistance compared to pure zinc platings. The state-of-the-art plating systems in the brake caliper industry are acid zinc-nickel electrolytes, as only they allow for direct plating on cast iron. Cast iron is the most common base material for the production of automotive brake components due to excellent mechanical and thermal properties. Well suited coatings will preserve the functional properties and provide additional advantages like improved corrosion protection and homogeneous and long lasting appearance. Consistently increasing quality demands, extended warranty periods and cost pressure lead to further developments and force the industry to look for new solutions.
2017-09-17
Journal Article
2017-01-2523
Seonho Lee, Yoongil Choi, Kyuntaek Cho, Hyounsoo Park
Abstract Raceway Brinell damage is one major cause of wheel bearing (hub unit) noise during driving. Original Equipment Manufacturer (OEM) customers have asked continuously for its improvement to the wheel bearing supply base. Generally, raceway Brinelling in a wheel hub unit is a consequence of metallic yielding from high external loading in a severe environment usually involving a side impact to the wheel and tire. Thus, increasing the yielding strength of steel can lead to higher resistance to Brinell damage. Both the outer ring and hub based on Generation 3 (Gen. 3) wheel unit are typically manufactured using by AISI 1055 bearing quality steel (BQS); these components undergo controlled cooling to establish the core properties then case hardening via induction hardening (IH). This paper presents a modified grade of steel and its IH design that targets longer life and improves Brinell resistance developed by ILJIN AMRC (Advanced Materials Research Center).
2017-09-17
Journal Article
2017-01-2524
Sebastiano Rizzo, Stefano Pagliassotto
Abstract Wheel bearings are safety-critical automotive components. For this application, the steel rolling elements are subjected to fatigue failure and therefore play a key role in overall bearing fatigue life performance. This performance is influenced by metallurgical, mechanical, and physical properties obtained by precise manufacturing process parameters. These properties are continuously analyzed and are evolving at all bearing manufacturing companies. Last year, the Precision Bearing Components (PBC) Group of NN Inc., a global supplier of steel rolling elements for wheel bearings, developed a non-conventional heat treatment process for 100Cr6 (SAE 52100) rolling element steel for improved fatigue performance. The results of wheel bearing rolling contact fatigue (RCF) tests showed the importance of rolling element dimensional stability. As retained austenite transformed to the martensite phase, rolling element volume increase occurred, leading to fatigue failure.
2017-07-10
Technical Paper
2017-28-1925
Asif Basha Shaik Mohammad, Ravindran Vijayakumar, Nageshwar Rao Panduranga
Abstract The automotive market has seen a steady increase in customer demands for quiet and more comfortable tractors. High noise at Operator Ear Level (OEL) of tractor is the major cause of fatigue to the operator. With growing competition, and upcoming legislative requirement there is ominous need for the agricultural tractor manufacturers to control noise levels. The objective of this study is noise reduction on agricultural tractor by stiffening sheet metal components. The design and analysis plays a major role for determining the root cause for the problem. Once the problem and its root cause were well defined, the solution for addressing the problem would be made clear. The engine excitation frequency and Sheet metal Components such as fender and platform natural frequency were coming closer and are leading to resonance.
2017-07-10
Technical Paper
2017-28-1962
Pervaz Ahmed Mouda, H Siddhi Jailani
Abstract Cryogenic treatment is an ultra low temperature treatment technique. Effect of cryogenic treatment on properties of ferrous materials and alloys is well understood. Due to which, cryogenic treated materials are being used in various applications. One among them is Electro-Discharge Machining (EDM). In EDM, the replica of electrode is obtained on the work piece, during the process tool also worn out to certain extent. In order to reduce the tool wear rate cryogenic treatment can be applied to the tool material. In this paper, the effect of cryogenic treatment on electrode wear rate of electro-discharge machining for varied pulse ON time (EDM) was studied. The cryogenic treatment was applied to the copper electrode and the microstructure analysis was carried out using optical microscope. EDM experiment was conducted using untreated and cryogenic treated copper as electrode and High Speed Steel (HSS) as work piece. Electrical resistivity was also measured.
2017-07-10
Technical Paper
2017-28-1969
Senthil Ram Nagapillai Durairaj, Thulasirajan Ganesan, Praveen Chakrapani Rao
Abstract Magnesium alloy current being used for automotive sector and are being significantly used for manufacturing engine block as offering higher power to weight ratio to the vehicle. In this context, the magnesium alloy has been used in the replacement of aluminium alloy for the starter housing which in turn increase the power to weight ratio of the motor. Considering the operation condition of starter motor in the engine of the vehicles, the starter motor is being exposed to the harsh environment, where its system is being tested for Noise, Vibration and Harshness. In this paper, the magnesium alloy housing is used to study the vibration and noise developed in the starter motor and the same is compared with the noise and vibration of the motor when it being used with Aluminium alloy Housing. First, the vibration study is carried out for the housing part alone to capture the resonant frequency of the both housing alloy say, Aluminium and Magnesium.
2017-07-10
Technical Paper
2017-28-1967
Senthil Ram Nagapillai Durairaj, Thulasirajan Ganesan, Praveen Chakrapani Rao
Abstract Global Automotive Industry is mandated with the task of emission reduction and mileage improvements. One of the key areas being looked at from mileage standpoint is light weighting. While Aluminum body is replacing Steel is many vehicular applications, in Starter Motor Aluminum is the key component. Therefore, any attempt at light weighting must consider Aluminum. A Starter motor fits directly on to the engine. Aluminum being the housing material provides structural stability. It also performs the role of heat dissipation being a good thermal conductor and source of electrical ground path. Aluminum constitutes 20 - 25% of Starter motor weight. Any significant weight reduction cannot be achieved unless we look at the components made of Aluminum, namely die cast Housing and End plate. The alternatives considered in this study include engineered plastics, magnesium alloy and composites.
2017-07-10
Technical Paper
2017-28-1986
Dinesh Paulraj, S.S.M Abdul Majeed, R Rajendran
Abstract In this study, the TiO2 nano particles are incorporated with A356 aluminium to form a Metal Matrix Composite (MMC) to be utilized in aerospace, marine, military and automotive applications. Stir casting method was used for producing the metal matrix composites. A356 aluminium was reinforced with various weight percentage (wt%) of TiO2 under 10 minutes holding time and 450 rpm stirring speed. Mechanical properties such as tensile strength and hardness of the Metal Matrix Composite were tested. Using Scanning electron microscope the surface morphology and composition of the manufactured specimens were studied. Energy dispersive spectroscopic analysis was carried out to study the elemental composition of the MMC. The mechanical tests reveal that there is a significant enhancement in the properties of the composites with 1.5 wt% of TiO2.
2017-07-10
Technical Paper
2017-28-1984
Naveed Hussain
Abstract Importance of fibers as reinforcements in metal matrices has long been recognized. It is only because of this realization that many industries like aerospace and to some extent the automobile industry relies entirely on advanced composite materials for their conflicting demands of high performance and lightweight materials. However most of the work in these areas has been limited or confined to patents created by the defense and automotive sectors. The efforts to commercialize these materials have been restricted due to high cost of the reinforcements and the manufacturing processes used. In this work an attempt has been made to infiltrate the Carbon fibers by imparting Nickel and Salt based coatings to fiber surfaces with commercial purity aluminum and A356 alloy. Infiltration has been performed in ambient atmosphere and also under vacuum. The carbon fibers have been successfully infiltrated with K2ZrF6 salt coatings and were hot pressed to required shapes.
2017-03-28
Technical Paper
2017-01-1704
D.J. Branagan, A.E. Frerichs, B.E. Meacham, S. Cheng, A.V. Sergueeva
Abstract Automotive OEMs are compelled by increasingly stringent global emissions standards to find economic solutions for building higher efficiency vehicles without compromising safety and ride quality. This challenge requires new advanced high strength steels (AHSS) that will significantly reduce vehicle weight and improve fuel economy. In addition to providing higher strength, these automotive sheet steels must have exceptional formability to produce reduced gauge parts with increasingly complex geometries. Formability is comprised of two components, global and local. Global formability represents the ability of a sheet material to be deformed under various stress conditions and to be formed into a part without failure. It can be estimated using forming-limit diagrams or ductility measurements from conventional uniaxial tensile tests. However, these tests cannot reliably assess the local formability at the edges or at the internal holes of the blanks during stamping.
2017-03-28
Technical Paper
2017-01-1708
Saeid Nasheralahkami, Sergey Golovashchenko, Collin Malek, Erika Rugh, Daniel Kowalsky, Weitian Zhou
Abstract In recent years, dual phase (DP) Advanced High Strength Steels (AHSS) and Ultra High Strength Steels (UHSS) are considered as prominent materials in the automotive industry due to superior structural performance and vehicle weight reduction capabilities. However, these materials are often sensitive to trimmed edge cracking if stretching along sheared edge occurs in such processes as stretch flanging. Another major issue in the trimming of UHSS is tool wear because of higher contact pressures at the interface between cutting tools and sheet metal blank caused by UHSS’s higher flow stresses and the presence of a hard martensitic phase in the microstructure. The objective of the current paper is to study the influence of trimming conditions and tool wear on quality and stretchability of trimmed edge of DP980 steel sheet. For this purpose, mechanically trimmed edges were characterized for DP980 steel and compared with other steels such as HSLA 350 and BH210.
2017-03-28
Technical Paper
2017-01-1706
Sandeep Bhattacharya, Daniel Green, Raj Sohmshetty, Ahmet Alpas
Abstract Automobile body panels made from advanced high strength steel (AHSS) provide high strength-to-mass ratio and thus AHSS are important for automotive light-weighting strategy. However, in order to increase their use, the significant wear damage that AHSS sheets cause to the trim dies should be reduced. The wear of dies has undesirable consequences including deterioration of trimmed parts' edges. In this research, die wear measurement techniques that consisted of white-light optical interferometry methods supported by large depth-of-field optical microscopy were developed. 1.4 mm-thick DP980-type AHSS sheets were trimmed using dies made from AISI D2 steel. A clearance of 10% of the thickness of the sheets was maintained between the upper and lower dies. The wear of the upper and lower dies was evaluated and material abrasion and chipping were identified as the main damage features at the trim edges.
2017-03-28
Technical Paper
2017-01-0476
Seiji Furusako, Masatoshi Tokunaga, Masanori Yasuyama
Abstract To reduce the weight of automobile bodies, application of high-strength steel sheets is expanding. Furthermore, middle and high carbon steels are expected to be used to lower the environmental impact and cost in the automobile steel sheet industry. However, it is necessary to enhance the joint strength of the steel sheets. In this study, hat-shaped components were made using resistance spot (RS) welding or arc spot (AS) welding on S45C steel sheets (including 0.44% carbon), 1.4 mm thickness and strength of 1180 MPa grade. A dynamic three-point bending test was conducted on the components and their crashworthiness was compared. Some RS welds fractured (separated) during the three-point bending test even though the diameter of the weld metal was increased to 5√t (t means thickness of the sheet); however, AS welds did not fracture.
2017-03-28
Technical Paper
2017-01-0472
Gyoko Oh
Abstract To prevent corrosion of the inlet part with aqueous ammonia injection, high chromium corrosion-resistant materials have been applied for welded joints of mufflers. Bending fatigue strength of welded joint samples of flange pipes was defined through fatigue experiments, modeling that high fluctuating stresses exist in the inlet and outlet flange pipes of a muffler caused by the vibration of a moving vehicle. Factors that caused fatigue to failure such as welding bead shape and metallographic structure were identified through local stress measurements, FEM stress simulations, microscopic observations, and SEM-EDS composition analyses. By comparing with sample A having a smaller flank angle and sample B having a larger flank angle, the results suggested that the difference of bending fatigue strengths at 200,000 cycles was 24% when based on nominal stress, and the difference was 10% when based on measured maximum stress.
2017-03-28
Technical Paper
2017-01-0506
Xueyuan Nie, Jimi Tjong
Abstract Ultra-high strength steel (UHSS) and magnesium (Mg) alloy have found their importance in response to automotive strategy of light weighting. UHSS to be metal-formed by hot stamping usually has a hot-dipped aluminum-silicon alloy layer on its surface to prevent the high temperature scaling during the hot stamping and corrosion during applications. In this paper, a plasma electrolytic oxidation (PEO) process was used to produce ceramic oxide coatings on aluminized UHSS and Mg with intention to further improve their corrosion resistances. A potentiodynamic polarization corrosion test was employed to evaluate general corrosion properties of the individual alloys. Galvanic corrosion of the aluminized UHSS and magnesium alloy coupling with and without PEO coatings was studied by a zero resistance ammeter (ZRA) test. It was found that the heating-cooling process simulating the hot stamping would reduce anti-corrosion properties of aluminized UHSS due to the outward iron diffusion.
2017-03-28
Technical Paper
2017-01-0502
Mingde Ding, Jiancai Liu, Jianbo Su, Zhong Su, Bo Liu, Ligang Wang
Abstract Now weight reduction is increasingly needed in automotive industry to improve fuel efficiency and to reduce emission. Various lightweight technologies have been used to vehicles. Because of its heavy weight and complex shape, IP carrier tends to be integration and weight intensive. Therefore lightweight is necessary for IP carrier. This paper lists the fourth lightweight technologies used for IP carrier by now, which are Magnesium alloy part, Aluminum alloy part, Hybrid composite part, Composite material injection part. For magnesium alloy part and aluminum alloy part, they have been mass produced for some years. The hybrid composite part has been researched for some years. Recently, the injection composite part has been researched and some parts have been developed and tested. By outlining the design, manufacturing, weight reduction and cost of these lightweight technologies, this paper fully analyzed these used technologies.
2017-03-28
Technical Paper
2017-01-0286
Amrinder Singh, Abhishek Ramakrishnan, Guru Dinda
Abstract Additive manufacturing (AM) of metals is finding numerous applications in automotive industry. In 21st century, aluminum is second to steel in automotive sector, because of its high strength to weight ratio. Hence developing AM for aluminum alloys become necessary to make sure industry gains maximum benefit from AM. This study specifically deals with the manufacturing of Al 7050 alloy, which is quite hardest alloy to manufacture using AM. The ultimate goal is to optimize the laser deposition parameters to deposit defect free Al 7050 alloy on rolled aluminum alloy substrate. Parameter optimization (laser power, powder flow rate, and scanning speed) gets difficult with the presence of various low melting and boiling point alloying elements such as Zn, Mg etc. Numerous other challenges faced while depositing Al 7050 alloy, are also briefly discussed in this article.
2017-03-28
Technical Paper
2017-01-0283
Mohammad K. Alam, Navid Nazemi, Ruth Jill Urbanic, Syed Saqib, Afsaneh Edrisy
Abstract Laser cladding is a novel process of surface coating, and researchers in both academia and industry are developing additive manufacturing solutions for large, metallic components. There are many interlinked process parameters associated with laser cladding, which may have an impact on the resultant microhardness profile throughout the bead zone. A set of single bead laser cladding experiments were done using a 4 kW fiber laser coupled with a 6-axis robotic arm for 420 martensitic stainless steel powder. A design of experiments approach was taken to explore a wide range of process parameter settings. The goal of this research is to determine whether robust predictive models for hardness can be developed, and if there are predictive trends that can be employed to optimize the process settings for a given set of process parameters and microhardness requirements.
2017-03-28
Technical Paper
2017-01-0285
Navid Nazemi, Mohammad K. Alam, Ruth Jill Urbanic, Syed Saqib, Afsaneh Edrisy
Abstract Laser cladding is used to coat a surface of a metal to enhance the metallurgical properties at the surface level of a substrate. For surface cladding operations, overlapping bead geometry is required. Single bead analyses do not provide a complete representation of essential properties; hence, this research focuses on overlapping conditions. The research scope targets the coaxial laser cladding process specifically for P420 stainless steel clad powder using a fiber optic laser with a 4.3 mm spot size on a low/medium carbon structural steel plate (AISI 1018). Many process parameters influence the bead geometrical shape, and it is assumed that the complex temperature distributions within the process could cause subsequent large variations in hardness values. The bead overlap configurations experiments are performed with 40%, 50% and 60% bead overlaps for a three-pass bead formation.
2017-03-28
Technical Paper
2017-01-0396
Guobiao Yang, Changqing Du, Dajun Zhou, Hao Wang, Elizabeth Lekarczyk, Lianxiang Yang
Abstract Vehicle weight reduction is a significant challenge for the modern automotive industry. In recent years, the amount of vehicular components constructed from aluminum alloy has increased due to its light weighting capabilities. Automotive manufacturing processes, predominantly those utilizing various stamping applications, require a thorough understanding of aluminum fracture predictions methods, in order to accurately simulate the process using Finite Element Method (FEM) software or use it in automotive engineering manufacture. This paper presents the strain distribution of A5182 aluminum samples after punch impact under various conditions by Digital Image Correlation (DIC) system, its software also measured the complete strain history, in addition to sample curvature after it was impacted; therefore obtaining the data required to determine the amount of side-wall-curl (Aluminum sheet springback) present after formation.
2017-03-28
Technical Paper
2017-01-0394
Junrui Li, Ruiyan Yang, Zhen Li, Changqing Du, Dajun Zhou, Lianxiang Yang
Abstract Advanced high-strength steel (AHSS) is gaining popularity in the automotive industry due to its higher final part strength with the better formability compares to the conventional steel. However, the edge fracture occurs during the forming procedure for the pre-strained part. To avoid the edge fracture that happens during the manufacturing, the effect of pre-strain on edge cracking limit needs to be studied. In this paper, digital image correlation (DIC), as an accurate optical method, is adopted for the strain measurement to determining the edge cracking limit. Sets of the wide coupons are pre-strained to obtain the samples at different pre-strain level. The pre-strain of each sample is precisely measured during this procedure using DIC. After pre-straining, the half dog bone samples are cut from these wide coupons. The edge of the notch in the half dog bone samples is created by the punch with 10% clearance for the distinct edge condition.
2017-03-28
Technical Paper
2017-01-1666
David Weiss, Orlando Rios
Abstract Aluminum alloys containing cerium have excellent castability and retain a substantial fraction of their room temperature strength at temperatures of 200°C and above. High temperature strength is maintained through a thermodynamically trapped, high surface energy intermetallic. Dynamic load partitioning between the aluminum and the intermetallic increases mechanical response. Complex castings have been produced in both permanent mold and sand castings. This versatile alloy system, using an abundant and inexpensive co-product of rare earth mining, is suitable for parts that need to maintain good properties when exposed to temperatures between 200 and 315°C.
2017-03-28
Technical Paper
2017-01-1665
Qigui Wang, Peggy Jones, Yucong Wang, Dale Gerard
Abstract With the increasing use of aluminum shape castings in structural applications in automobiles, assurance of cast product integrity and performance has become critical in both design and manufacturing. In this paper, the latest understanding of the relationship between casting quality and mechanical properties of aluminum castings is summarized. Examples of newly developed technologies for alloy design, melting and melt treatment, casting and heat treatment processes in aluminum casting are reviewed. Robust design and development of high integrity aluminum castings through an Integrated Computational Materials Engineering (ICME) approach is also discussed.
2017-03-28
Technical Paper
2017-01-1663
Alan Druschitz, Christopher Williams, Erin Connelly, Bob Wood
Abstract Binder jetting of sand molds and cores for metal casting provides a scalable and efficient means of producing metal components with complex geometric features made possible only by Additive Manufacturing. Topology optimization software that can mathematically determine the optimum placement of material for a given set of design requirements has been available for quite some time. However, the optimized designs are often not manufacturable using standard metal casting processes due to undercuts, backdraft and other issues. With the advent of binder-based 3D printing technology, sand molds and cores can be produced to make these optimized designs as metal castings.
Viewing 1 to 30 of 4670