Centrifugally Cast Metallurgical Coatings for Wear Resistance in Plastics Molding Machines

1978 ◽  
Vol 100 (3) ◽  
pp. 423-427 ◽  
Author(s):  
G. A. Saltzman
Keyword(s):  
Wear Resistance ◽  
Base Alloy ◽  
Centrifugal Casting ◽  
Casting Process ◽  
Operating Conditions ◽  
Alloy Matrix ◽  
Centrifugally Cast ◽  
Wear Resistant Coatings ◽  
Industry Standard ◽  
Abnormal Operating Conditions

In extrusion and injection molding, centrifugally cast metallurgical coatings are often utilized to provide wear resistance in the barrel of the molding machine. The need for wear resistance is a result of two potential sources of wear, a screw or plunger that operates within the barrel, and the plastic being processed. Adhesive wear occurs under abnormal operating conditions when the screw bears against the barrel bore. Abrasive wear may result from certain additives used to modify the properties of the plastics. An in situ centrifugal casting process used for production of wear resistant coatings metallurgically bonded to the bores of heavy wall metal tubes is described. Characteristics of industry standard metallurgical coating alloys, a martensitic white iron, a Co-Ni-Cr-B alloy and a composite with tungsten carbide dispersed in a Ni-base alloy matrix are given. Metal-to-metal wear-compatibility tests are discussed.

Effect of Heat Treatment on Mechanical and Tribological Properties of Centrifugally Cast Functionally Graded Cu/Al2O3 Composite

2017 ◽  
Vol 140 (2) ◽  
Author(s):  
Manu Sam ◽  
N. Radhika
Keyword(s):  
Heat Treatment ◽  
Wear Resistance ◽  
Centrifugal Casting ◽  
Casting Process ◽  
Sem Analysis ◽  
Functionally Graded ◽  
Dry Sliding Wear ◽  
Centrifugally Cast ◽  
Mechanical And Tribological Properties ◽  
Different Temperatures

A functionally graded Cu–10Sn–5Ni metal matrix composite (MMC) reinforced with 10 wt % of Al2O3 particles was fabricated using the centrifugal casting process with dimension Φout100 × Φin85 × 100 mm. The mechanical and wear resistance of the composite has been enhanced through heat treatment. Samples from of the inner zone (9–15 mm) were considered for heat treatment, as this zone has higher concentration of less dense hard reinforcement particles. The samples were solutionized (620 °C/60 min) and water quenched followed by aging at different temperatures (400, 450, and 550 °C) and time (1–3 h). Optimum parametric combination (450 °C, 3 h) with maximum hardness (269 HV) was considered for further analysis. Dry sliding wear experiments were conducted based on Taguchi's L27 array using parameters such as applied loads (10, 20, and 30 N), sliding distances (500, 1000, and 1500 m), and sliding velocities (1, 2, and 3 m/s). Results revealed that the wear rate increased with load and distance whereas it decreased initially and then increased with velocity. Optimum condition for maximum wear resistance was determined using signal-to-noise (S/N) ratio. Analysis of variance (ANOVA) predicted the major influential parameter as load, followed by velocity and distance. Scanning electron microscope (SEM) analysis of worn surfaces predicted the wear mechanism, observing more delamination due to increase in contact patch when applied load increased. Results infer 8% increase in hardness after heat treatment, making it suitable for load bearing applications.

Measurement of Cooling Curves in Centrifugal Casting of a Ferrous Alloy

2008 ◽  
Author(s):  
Romulo Heringer ◽  
Ma´rio Boccalini ◽  
Marcelo A. Martorano ◽  
Cla´udia R. Serantoni
Keyword(s):  
High Temperature ◽  
Metal Layer ◽  
Centrifugal Casting ◽  
Thermal Characteristics ◽  
Thermal Inertia ◽  
Casting Process ◽  
Ferrous Alloy ◽  
Cooling Curves ◽  
Centrifugally Cast ◽  
Surrounding Liquid

A sensor was developed to measure the cooling curves inside a ferrous alloy during its solidification as centrifugally cast tubes. The temperature evolution at some points within the alloy is necessary to evaluate the heat transfer through the outer surface of the tube during the centrifugal casting process. Serious difficulties exist in this type of measurement, because of the rotation of the mold and the relatively high temperature at which the ferrous alloy is poured. The sensor consists of sheathed thermocouples positioned by a convenient support internally to the rotating mold, within the metal layer. Although the sensor is subjected to thermal and mechanical stresses during the melt pouring and solidification, it must maintain its mechanical and thermal characteristics to temperatures of the order of the melting point of the ferrous alloy. Therefore, the thermocouple sheaths and support have been made of refractory metals, namely, tantalum and niobium, to resist the high temperature. Moreover, the sensor was designed to have low thermal inertia, allowing its temperature to increase above the liquidus temperature of the alloy before solidification of the surrounding liquid metal. Because the sensor is embedded in the solidified tube after solidification, a special design was necessary to allow stripping the tube out of the mold without disturbing the system.

Interfacial Characteristics and Wear Resistance of WCp/White-Cast-Iron Composites

2007 ◽  
Vol 26-28 ◽  
pp. 293-296 ◽  
Author(s):  
Guo Shang Zhang ◽  
Yi Min Gao ◽  
Jian Dong Xing ◽  
Shi Zhong Wei ◽  
Xi Liang Zhang
Keyword(s):  
Wear Resistance ◽  
Cast Iron ◽  
White Cast Iron ◽  
Centrifugal Casting ◽  
Casting Process ◽  
Iron Matrix ◽  
High Chromium ◽  
X Ray ◽  
High Chromium Cast Iron ◽  
Wear Tests

To improve the wear resistance of high chromium white cast iron under severe abrasive conditions, a composites layer was designed for wear surface, which were locally reinforced with WC particles. And the local composites were successfully fabricated by optimized centrifugal casting process. Then the interface between WC and iron matrix was analyzed with scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). And three body wear tests were carried out on a self-made rig to investigate the wear resistance of the composites. For comparison, the wear tests of high chromium white cast iron were also carried out under the same conditions. The results show that: There are no defects such as inclusion, crack, gas pore and so on in the obtained composites layer, which with a uniform thickness of 10 mm. WC particles are homogeneously distributed in the composites layer and tightly bonded with the iron matrix. The WC particles are partially dissolved in the iron matrix during centrifugal casting. The elements W, C and Fe react to form new carbides such as Fe3W3C or M23C6, which precipitate around former WC particles during subsequent solidification. So the interface between WC particles and the iron matrix is a strong metallurgical bonding. WC particles in the composites layer can effectively resist cutting by the abrasive, and then protect the matrix. The wear resistance of the composites layer is 7.23 times of that of high chromium cast iron.

To Study the Role of WC Reinforcement and Deep Cryogenic Treatment on AZ91 MMNC Wear Behavior Using Multilevel Factorial Design

2019 ◽  
Vol 141 (4) ◽  
Author(s):  
P. Karuppusamy ◽  
K. Lingadurai ◽  
V. Sivananth
Keyword(s):  
Wear Resistance ◽  
Factorial Design ◽  
Wear Behavior ◽  
Base Alloy ◽  
Cryogenic Treatment ◽  
Casting Process ◽  
Frictional Heat ◽  
Dry Sliding Wear ◽  
Deep Cryogenic Treatment ◽  
Metal Matrix Nanocomposites

The present investigation explores the collective outcome of hard particle reinforcement with deep cryogenic treatment (DCT) on wear responses of magnesium metal matrix nanocomposites (MMNC). A multilevel factorial design of experiments with control factors of applied load (20 and 40 N), sliding speed (1.3, 1.7, 2.2, and 3.3 m/s), reinforcement % (0% and 1.5%), and cryogenic treatment (cryogenic-treated and nontreated) was deployed. Around 1.5 wt % WC-reinforced MMNC were fabricated using stir-casting process. DCT was performed at −190 °C with soaking time of 24 h. The dry sliding wear trials were done on pin-on-disk tribometer with MMNC pin and EN8 steel disk for a constant sliding distance of 2 km. The WC reinforcement contributed toward the improvement in wear rate of MMNC appreciably by absorbing the load and frictional heat at all loads and speeds. During DCT of AZ91, the secondary ß-phase (Mg17Al12) was precipitated that enriched the wear resistance, only for the higher load of 40 N. Scanning electron microscope analyses of the cryogenic-treated MMNC ensured the existence of both ß-phase precipitates and WC in the contact area. As a result, the adhesiveness of this pin was lesser, which attributed to the improved wear resistance (approximately 33%) as compared to base alloy. The coefficient of friction was also less for cryogenic-treated MMNC. A regression analysis was made to correlate the control elements and the responses.

DURALCAN W2FxxA

Alloy Digest ◽  
1995 ◽  
Vol 44 (7) ◽  
Keyword(s):  
Fracture Toughness ◽  
Wear Resistance ◽  
Aluminum Alloy ◽  
High Temperature ◽  
Base Alloy ◽  
Volume Percent ◽  
Alloy Matrix ◽  
Temperature Performance ◽  
Aluminum Alloy Matrix ◽  
Wrought Aluminum

Abstract DURALCAN W2F.xxA is a heat-treatable wrought aluminum alloy matrix composite, where xx represents the volume percent of alumina particulate, Al2O3. The base alloy is aluminum 2618 (Alloy Digest Al-76, February 1959). This datasheet provides information on composition, physical properties, microstructure, elasticity, and tensile properties as well as fracture toughness and fatigue. It also includes information on high temperature performance and wear resistance. Filing Code: AL-337. Producer or source: Duralcan USA.

scholarly journals Effect of ZrO2 Addition on Microstructure and Mechanical Properties of Al-Zn-Mg Alloy Matrix Composite

2020 ◽  
Vol 38 (12A) ◽  
pp. 1751-1757
Author(s):  
Israa A. Aziz ◽  
Russul S. Bedien
Keyword(s):  
Mechanical Properties ◽  
Composite Materials ◽  
Matrix Composite ◽  
Base Alloy ◽  
Casting Process ◽  
Optical Microscope ◽  
Industrial Applications ◽  
Unreinforced Alloy ◽  
Alloy Matrix ◽  
Weight Percentage

Aluminum – based metal matrix composite are widely used in industrial   applications compared with conventional and unreinforced alloy. The composite materials usually exhibit a higher strength both at elevated and ambient temperature, as well as wear resistance. The production of composite materials which contain different weight percentage of ZrO2 (0.5, 1.5 and 2.5wt %) by stir casting process. The mechanical properties of the base alloy and composite were evaluated   by using   tensile and hardness tests. The microstructure inspection by optical microscopy, scanning electron microscope and energy dispersive spectroscopy (EDS) were utilized to study the fracture surface topography. The results represent that the hardness, strength of yield and tensile strength increased with increasing the weight % of ZrO2 to 2.5 % while the elongation decreased. The microstructure inspection by optical microscope shows that the dendrites structure and the particles distribution in matrix without any voids. Furthermore, the grain size refining with the weight percentage of weight reinforcement elevated.                         

DURALCAN W6A.xxA

Alloy Digest ◽  
1995 ◽  
Vol 44 (4) ◽  
Keyword(s):  
Fracture Toughness ◽  
Wear Resistance ◽  
Aluminum Alloy ◽  
Base Alloy ◽  
Corrosion And Wear ◽  
Volume Percent ◽  
Alloy Matrix ◽  
Temperature Performance ◽  
Aluminum Alloy Matrix ◽  
Wrought Aluminum

Abstract DURALCAN W6A.xxA is a heat-treatable wrought aluminum alloy matrix composite, where xx represents the volume percent of alumina particulate, Al2O3. The base alloy is 6061 (Alloy Digest Al-205, January 1973). This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as fracture toughness. It also includes information on high temperature performance, corrosion and wear resistance as well as machining. Filing Code: AL-333. Producer or source: Duralcan USA.

DELORO STELLITE 25

Alloy Digest ◽  
2021 ◽  
Vol 70 (11) ◽  
Keyword(s):  
Wear Resistance ◽  
Corrosion Resistance ◽  
Base Alloy ◽  
Chromium Alloy ◽  
Cobalt Chromium ◽  
Alloy Matrix ◽  
Cobalt Base Alloy ◽  
Cocr Alloy ◽  
Cobalt Base ◽  
Cobalt Chromium Alloy

Abstract Deloro Stellite 25 is a cobalt-chromium-tungsten-nickel alloy. This tungsten strengthened cobalt-chromium alloy is the cast version of the wrought cobalt-base alloy L605. Deloro Stellite 25 is resistant to wear, galling, and corrosion and retains this resistance at high temperatures. Its exceptional wear resistance is due mainly to the unique inherent characteristics of the hard carbide phase dispersed in a CoCr alloy matrix. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as machining. Filing Code: Co-142. Producer or source: Deloro Wear Solutions GmbH.

Effect of Copper and Magnesium on the Microstructure of Centrifugally Cast Al-19%Si Alloys

2018 ◽  
Vol 930 ◽  
pp. 484-488
Author(s):  
Chester Contatori ◽  
Antônio Augusto Couto ◽  
Jan Vatavuk ◽  
Arnaldo A. Ciquielo Borges ◽  
Nelson Batista de Lima ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Molten Metal ◽  
Centrifugal Casting ◽  
Intermetallic Phase ◽  
Outer Wall ◽  
Primary Silicon ◽  
Functionally Graded ◽  
High Wear Resistance ◽  
Centrifugally Cast ◽  
Β Phase

Hypereutectic Al-Si alloys can be used in applications that require high wear resistance. Such wear resistance is achieved by the presence of hard primary silicon particles, allied to the formation of Mg2Si intermetallic phase when magnesium is added in this alloy. Centrifugal casting generates a gradient in the microstructure of hypereutectic Al-Si alloys that can favor such applications. Cylindrical components of Al-19%Si alloy containing added copper and magnesium contents were processed by centrifugal casting. The purpose of this study is to investigate the formation and segregation of particles of primary silicon (β) and Mg2Si in Al-19%Si alloy containing additions of copper and magnesium. Because the density of silicon (2.33 g/cm3) and Mg2Si (1.88 g/cm3) is lower than that of aluminum (2.67 g/cm3), centrifugal casting causes primary silicon (β) and Mg2Si particles to concentrate more at the outer wall of the centrifuged pipe. In this study, primary silicon (β) and Mg2Si particles were found to be retained at the outer wall of the pipe. It is believed that the rapid cooling of the molten metal in the region of contact with the mold, whose temperature is lower than that of the molten metal, allied to the centrifugal force, prevented the particles from migrating to the inner wall of the pipe. The microstructure shows a gradient in the distribution of these phases, enabling the production of a functionally graded material. The addition of copper and magnesium leads to the formation of Mg2Si and Al5Cu2Mg8Si6 phases, reducing the amount of primary β phase (Si) particles. In all the evaluated conditions, a tendency is also observed for a gradual increase in the segregation of silicon towards the inner wall along the entire length of the centrifuged pipe.

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