Phosphor Bronze Research Articles

Effect of thermomechanical processing on the grain boundary character distribution of phosphorus bronze

Grain boundary engineering (GBE) is widely adopted to improve the grain boundary (GB) character distribution (GBCD) of face-centered-cubic (FCC) metals. In phosphorus bronze alloy, achieving an optimized GBCD while maintaining sufficiently small grain size is critical for maintaining high strength and excellent bending workability. However, the precise evolution and formation mechanisms of GBs during GBE remain unclear to date. Leveraging electron backscatter diffraction and transmission electron microscopy analyses, this study examined the effect of thermomechanical processing (TMP) on GBCD optimization and twin-related domain (TRD) evolution in phosphorus bronze. The results revealed that strain-induced boundary migration (SIBM) plays a pivotal role in GBCD optimization. In particular, SIBM facilitates the formation of abundant new Σ3 boundaries behind migrating GB fronts, thus increasing the proportion of special boundaries (SBs) and introducing low-energy segments such as Σ9 and Σ27 boundaries. These boundaries effectively disrupt the connectivity of the random high angle grain boundary (RHAGB) network. Furthermore, the results indicate that the optimal TMP conditions for GBCD optimization include a reduction level of 5 %, annealing temperature of 450 °C, and annealing duration of 1 h. These conditions result in an average grain size being <3 μm and the GB fractions fSBs and fΣ9+Σ27 being 81.3 % and 9.8 %, respectively. Deformation twins formed within the deformed microstructure inhibit TRD growth, thus hindering GBCD optimization. Additionally, the optimal strain threshold for GBCD optimization lies near the strain threshold for the formation of deformation twins. TRDs form during the primary recrystallization process, while high-order twin boundaries form behind the migration front during the growth process.

Acoustic noise reduction in the NexGen 7 T scanner.

Driven by the Lorentz force, acoustic noise may arguably be the next physiological challenge associated with ultra-high field MRI scanners and powerful gradient coils. This work consisted of isolating and mitigating the main sound pathway in the NexGen 7 T scanner equipped with the investigational Impulse head gradient coil. Sound pressure level (SPL) measurements were performed with and without the RF coil to assess its acoustic impact. Vibration measurements were carried out on the gradient coil, the RF coil, and on the patient table to distinguish the different vibration mechanisms and pathways. Vibrations of the RF coil were modified by either making contact with the patient bore liner with padding material or by changing directly the RF shield with phosphor bronze mesh material. SPL and vibration measurements demonstrated that eddy-currents induced in the RF shield were the primary cause of acoustic noise. Replacing the conventional solid copper shield with phosphor bronze mesh material altered the vibrations of the RF shield and decreased SPL by 6 to 8 dB at the highest frequencies in EPI, depending on the gradient axis, while boosting the transmit B1 + field by 15%. Padding led to slightly less sound reduction on the X and Z gradient axes, but with minimal impact for the Y axis. This study demonstrates the potential importance of eddy-current induced vibrations in the RF coil in terms of acoustic noise and opens new horizons for mitigation measures.

Performance of Structured Packing for the Deuterated Water Distillation Process at Above Atmospheric Pressure

The National Research and Development Institute for Cryogenics and Isotopic Technologies (ICSI) was established in 1970 for research focused the industrial pilot plant. ICSI was created with the purpose of developing the heavy water production technology needed mainly for the operation of the CANDU reactors that equip the Cernavoda Nuclear Power Plant in Romania. This technology has been demonstrated and has been successfully transferred to the heavy water production plant. The accumulated experience in the field of isotopic separation allowed for the development of a second pilot plant, also for the purpose of heavy water, but this time for the purpose of separating deuterium and tritium for the recovery of tritium, mainly from the tritiated heavy water of the CANDU reactors. This experimental pilot is based on a technology that combines two hydrogen isotope separation processes: liquid-phase water-hydrogen catalytic isotopic exchange and hydrogen isotope cryogenic distillation. The success of the separation process consists of the technical solution given to the exchange area, its geometry (distillation-isotopic exchange), and last but not least, the performance of the hydrophilic packing, respectively, of the catalyst. Thus, an extensive research program was initiated and carried out over many years for the development of mixed catalytic packages consisting of a hydrophobic Pt/carbon catalyst (with different concentrations of platinum up to 2%) and hydrophilic packing (stainless steel or phosphorous bronze) manufactured within ICSI and made in different configurations (successive layers, random or structured). This program for the improvement of catalytic packages continues by implementing new solutions regarding the improvement of materials that ensure a large contact surface between the liquid and vapors, respectively, vapor and gas, thus increasing the isotopic separation performance. This paper presents an experimental analysis of two types of hydrophilic stainless steel packings developed for the purpose of separating hydrogen isotopes by water distillation to be used in the manufacture of mixed catalytic packages for the catalytic isotopic exchange process. This paper refers to the experiments performed with deuterated water on the hydrophilic packing in conditions of total reflux. The experiments were performed on a column equipped with two types of hydrophilic packing.

Achievement of heat treatment strengthening in phosphor bronze through semi-coherent precipitation

Traditional phosphor bronzes have faced difficulties in terms of strengthening via heat treatment. In this study, a Cu-Sn-P-Ni-Si alloy with capability of precipitation strengthening was designed based on phase diagram calculations. After direct aging treatment, the mechanical properties of the Cu-8Sn-0.1P alloy exhibit minimal changes. However, significant strengthening was achieved in the Cu-Sn-P-Ni-Si alloy. Experimental results demonstrate that during the direct aging process, semi-coherent interfaces are formed between the precipitate phases and the matrix in Cu-8Sn-0.1P-1Ni-0.227Si alloy, resulting in significant performance enhancement. Specifically, the yield strength of the alloy was increased by approximately 39% after aging treatment. Crucially, the strengthening mechanism of the Cu-Sn-P-Ni-Si alloy and the formation mechanism of semi-coherent interfaces were elucidated. This work provides a method to significantly enhance the comprehensive performance of phosphor bronze without requiring any special additional manufacturing processes. The achievement of heat treatment strengthening of phosphor bronze without undergoing deformation processing will enhance its potential for application.

Experimental evaluation of tribo-performances of bump foil journal bearing with different materials of foil

In this paper, the bump foil journal bearing (FJB) is developed with five different foil materials: Inconel X750 (IN-X750), Stainless steel 316 (SS316), Beryllium copper (BC), Spring steel EN42J (SP EN42J) and Phosphor bronze (PB). A complete fabrication process is described in detail, along with the design of fixtures, to develop the bump FJB. This fabrication process includes various machining operations such as milling, rolling, cutting, threading, forming etc. The forming load versus deflection curve is obtained for all the foil materials with the metal forming operation. After fabricating it, the load-deflection test is performed to evaluate the structural characteristics (stiffness, energy dissipation and damping coefficient) of these developed bump FJB. Further, the tribological characteristics of bump FJB such as wear rate and surface roughness are evaluated by the experimental study. Moreover, the interface temperature of bump FJB is also captured by using the thermal imager. This study shows that the metal forming operation is the most challenging step among all the fabrication steps of bump FJB Among all the foil materials, the minimum wear rate and maximum surface roughness of bump FJB are observed for the IN-X750. The maximum spring-back effect in bump FJB is found for the Spring steel EN42J. These results demonstrate that the maximum energy dissipation and stiffness of bump FJB are observed for the Phosphor bronze and Inconel-X750 respectively. In addition, the damping coeffcient of bump FJB is evaluated.

A failure analysis of foil journal bearing under low-speed operating conditions

In this failure analysis, the bump-type foil journal bearing (BFJB) is developed with various foil materials such as spring steel EN42J, phosphor bronze, Inconel X750, and SS 316. Subsequent failure analysis of the BFJB is conducted under low-speed operating conditions to evaluate their rubbing performance using the RSM technique. The study examined rotor speed and load as variable parameters, with wear rate (WR) and surface roughness (SR) of the BFJB as output responses. Additionally, a thermal imager is used to measure the rubbing temperature of the BFJB. The results indicated that Inconel X750 demonstrated superior tribological characteristics for the BFJB. With an increase in load, the wear rate of the BFJB increased while the surface roughness decreased. Among all foil materials, Inconel X750 had the most significant impact on surface roughness. The optimal values for rotor speed (S) and load (P) to enhance BFJB performance are 500 rpm and 10 N, respectively. Under these optimal conditions, the BFJB with Inconel X750 as the foil material exhibited a wear rate of 0.0150 mg/s and a surface roughness of 2.085 μm. Moreover, the BFJB made with phosphor bronze displayed the minimum rubbing temperature.

Magnetic-Controlled Short Process Preparation Technique for Phosphor Bronze Based on Structure Refinement

Magnetic-Controlled Short Process Preparation Technique for Phosphor Bronze Based on Structure Refinement

Comparative study on tribological behavior of foil journal bearings with micro pocket

Abstract This study explores the tribological performance of bump foil journal bearing (FJB) equipped with micro-pocket. The influence of micro-pocket on the load capacity (LC) and friction factor (FF) of FJBs is evaluated for various foil materials, including Inconel X750 (IN), Spring steel EN42J (SP), SS 316, Beryllium copper (BC), and Phosphor bronze (PB). The compressible Reynolds equation is solved numerically to assess the tribological behavior of bump FJB under various operating conditions. Initially, the impact of micro pocket on the tribological characteristics such as load capacity and friction factor of bump FJB is examined by comparing their performance with plain FJB. Subsequently, the effect variable parameters such as pocket depth (PD), bearing number (Λ), and eccentricity ratio (ε), on the tribological behavior is analysed by using response surface methodology (RSM). The multi-objective grey relational analysis (GRA) technique is employed to determine the optimal values of these variable parameters for each foils material. The findings reveal that micro-pocket enhance the dimensionless LC of bump FJB beyond a bearing number of 2.061. Moreover, micro-pocket reduce the friction factor of bump FJBs. Within the presence of micro pocket, SS 316 exhibits the most significant foil material for the better tribological characteristics of bump FJB, while phosphor bronze is the least signifcant. For SS 316, the optimal values of pocket depth (PD), bearing number (Λ), and eccentricity ratio (ε) are 3 μm, 2.061, and 0.5 respectively. Under these optimal conditions, the load capacity (LC) and friction factor (FF) of bump FJBs are 0.7740 and 13.645, respectively. Micro-pocket reduces the friction factor (FF) by 2 to 15%. The impact of pocket depth on the LC and FF of bump FJB is significant for the phosphor bronze. Additionally, increasing the pocket depth enhances the dimensionless LC of bump FJBs while decreasing the friction factor.

Mechanical properties and performance evaluation of aluminum nickel phosphorus bronze MMC reinforced with TiCN + SiC nanopowders for lightweight armored vehicles

Mechanical properties and performance evaluation of aluminum nickel phosphorus bronze MMC reinforced with TiCN + SiC nanopowders for lightweight armored vehicles

Mechanical and Corrosion Properties of Friction Stir Welded and Tungsten Inert Gas Welded Phosphor Bronze

Abstract This study investigated the mechanical and corrosion properties of Friction Stir Welded (FSW) and Tungsten Inert Gas (TIG) welded phosphor bronze (CuSn4) joints. Corrosion tests were conducted on the welded joints, and the percentage of weight loss due to corrosion was measured at different time intervals. Results revealed that the percentage of weight loss due to corrosion of the TIG joint increased with time, whereas the percentage of weight loss due to corrosion of the FSW welded joint remained constant. This could be attributed to recrystallisation that happened in the solid-state welding, which reduced corrosion in the FSW welded joint. In addition, tensile tests were conducted to evaluate the strength of the joints. FSW with a spindle speed of 1300 rpm, weld speed of 0.06mm/sec, plunge depth of 0.25mm, pin profile of pentagon, and flat shoulder profile was found to produce good results. TIG welding with a welding speed of 1.75mm/sec, a gas flow rate of 7.5 cm3/min and an amperage of 120A also produced good results. The tensile strength of FSW was found to be approximately 1.6 times higher than that of TIG welding.

Effects of Material Structure on Stress Relaxation Characteristics of Rapidly Solidified Al-Fe Alloy.

An Al-Fe alloy which was produced by hot extrusion of rapidly solidified powder is a possible solution to substitute copper-based electrical conductor material due to its high strength and high electrical conductivity. However, the stress relaxation characteristic-an essential parameter as a conductor material-and the effect of the material structure have not been reported, which was the aim of the present paper. An Al-5%Fe alloy was selected as the test material. The material structures were controlled by hot extrusion practice, annealing, and cold rolling. The Al-Fe intermetallic compound particles controlled the residual stress after the stress relaxation test via the Orowan mechanism. Decreasing the mean inter-particle distance reduces the electrical conductivity. The increase in the number of dislocations by the cold rolling increased strength at room temperature without changing electrical conductivity; however, it did not have a positive effect on the stress relaxation characteristics. The stress relaxation characteristics and the electrical conductivity of the Al-Fe alloy were superior to conventional C52100 H04 phosphor bronze when compared with the case of the same mass.

Investigation of Faraday cage materials with low eddy current and high RF shielding effectiveness for PET/MRI applications

Objective. This study aims to evaluate radiofrequency (RF) shielding effectiveness (SE), gradient-induced eddy current, magnetic resonance (MR) susceptibility, and positron emission tomography (PET) photon attenuation of six shielding materials: copper plate, copper tape, carbon fiber fabric, stainless steel mesh, phosphor bronze mesh, and a spray-on conductive coating. Approach. We evaluated the six shielding materials by implementing them on identical clear plastic enclosures. We measured the RF SE and eddy current in benchtop experiments (outside of the MR environment) and in a 3T MR scanner. The magnetic susceptibility performance was evaluated in the same MR scanner. Additionally, we measured their effects on PET detectors, including global coincidence time resolution, global energy resolution, and coincidence count rate. Main results. The RF SEs for copper plate, copper tape, carbon fiber fabric, stainless steel mesh, phosphor bronze mesh, and conductive coating enclosures were 56.8 ± 5.8, 63.9 ± 4.3, 33.1 ± 11.7, 43.6 ± 4.5, 52.7 ± 4.6, and 47.8 ±7.1 dB, respectively, in the benchtop experiment. Copper plate and copper tape experienced the most eddy current at 10 kHz in the benchtop experiment and also generated the largest ghosting artifacts in the MR scanner. Stainless steel mesh had the highest mean absolute difference (7.6 ±0.2 Hz) compared to the reference in the MR susceptibility evaluation. The carbon fiber fabric and phosphor bronze mesh enclosures caused the largest photon attenuation, reducing the coincidence count rate by 3.3%, while the rest caused less than 2.6%. Significance. The conductive coating proposed in this study is shown to be a high-performance Faraday cage material for PET/MRI applications based on its overall performance in all the experiments conducted in this study, as well as its ease and flexibility of manufacturing. As a result, it will be selected as the Faraday cage material for our second-generation MR-compatible PET insert.

Microstructure and Properties of Phosphorus Bronze/Brass Joints Produced by Resistance Projection Welding

In this work, we fabricated lap joints between embossed projection phosphorus bronze and flat brass through resistance projection welding (RPW). The experimental results indicated that the bronze projection moves into the softer brass without being deformed during the welding process. The tensile shear loads of the joint reached a maximum value of 273.6 N at a welding current of 5.5 kA. Under this circumstance, a reaction layer, including a columnar crystal solidification layer and a diffusion layer, is formed at the interface beside the boundary of bronze. The EDS line scan shows an elemental transition diffusion layer of about 1.5 μm between the H62 brass columnar crystal and XYK-6 phosphorus bronze. The fracture occurred on the XYK-6 side, passing through the bump instead of the welding interface, resulting in intactness of the welding interface. The results revealed that resistance projection welding is an effective method for welding copper alloys, suggesting the bright prospects of this technology in welding electrical parts.

Microstructures and properties of Ni-Si precipitation strengthened phosphor bronze

To strengthen phosphor bronze, this work attempted to form precipitate nanoparticles in the matrix by adding alloying elements. First, Ni and Si were identified as alloying elements through mixing enthalpy analysis. Then, Cu-8Sn-0.1P, Cu-8Sn-0.1P-0.5Ni-0.12Si, Cu-8Sn-0.1P-1Ni-0.24Si, and Cu-8Sn-0.1P-2Ni-0.48Si alloys were prepared by intermediate frequency induction furnace. After that, the microstructures of these alloys were characterized and their properties were tested. Experimental results indicated that Ni31Si12, Ni2Si, and Ni5P4 phases are newly formed in the as-cast microstructure after adding Ni and Si. At the same time, the eutectoid size of α-Cu and Cu41Sn11 in the as-cast microstructure of Ni-Si added phosphor bronze is reduced, the secondary dendrite arm spacing is reduced, and the segregation is also improved. After aging treatment, nano-sized cellular Ni2Si and trace Ni5P4 phases are precipitated in the Ni-Si added phosphor bronze. With the formation of nanoprecipitates, Ni-Si added phosphor bronzes show excellent precipitation strengthening effect after aging treatment, and the electrical conductivity of Cu-8Sn-0.1P-0.5Ni-0.12Si and Cu-8Sn-0.1P-1Ni-0.24Si alloys is also slightly higher than that of Cu-8Sn-0.1P. This study provides a new solution for strengthening phosphor bronze, enabling phosphor bronze alloys to meet higher performance and broader applications.

Improving output performance of ultrasonic motor by coating MoS2 on the stator

To improve the wear resistance of frictional interface of ultrasonic motors (USM), a new tribological pair was designed. The phosphor bronze stator surface of USM urgently needs modification to match with aluminum alloy rotor surface that was treated by micro-arc oxidation (MAO). The tribological properties of stator coating, MoS2 and WS2, were compared at the material level. The strengthening mechanism of stator coating was interpreted by extracting microscopic information from molecular dynamics (MD) results. The results showed that new tribological pair significantly enhance the output performance and energy conversion efficiency, particularly the MoS2 coating. When the preload was 280 N, input voltage was 500 V, and frequency was 36.2 kHz, the maximum efficiency of MoS2 reached to 46.12%.

Attenuation characteristics of tones and vibrations in guitars with nylon, fluorocarbon, and phosphor bronze strings pressed down against fret

Attenuation characteristics of tones and vibrations in guitars with nylon, fluorocarbon, and phosphor bronze strings pressed down against fret

Joining of Cast Iron and Phosphor Bronze Through Liquid–Solid Interaction: Effect of Ni and Cu Coating on Interfacial Microstructures and Mechanical Properties of Bimetallic Composites

Joining of Cast Iron and Phosphor Bronze Through Liquid–Solid Interaction: Effect of Ni and Cu Coating on Interfacial Microstructures and Mechanical Properties of Bimetallic Composites

Process study of copper preparation by FDM-assisted limited domain electrodeposition

A combination of Fused Deposition Modeling (FDM) and electrochemical deposition was used to prepare copper samples, and the influence of different copper anodes on the composition and microstructure of the prepared samples were investigated. It was shown that under the deposition conditions of constant current, the deposited products were mainly copper with trace impurity elements when brass, leaded brass, phosphor bronze, manganese copper, purple copper, and beryllium copper were used as anodes. The surface morphology of copper films obtained when brass was used as an anode was the flattest, and the thickness was also the largest. Electrodeposition experiments of 20 and 150 layers of copper samples were conducted using brass as the anode and the preliminary validation of FDM-assisted electrochemical additive manufacturing fabricating 3D solids.

Novel Synthetic ‘Triangle Ester’ Lubricants: Useful Correlations for Wetting and Tribological Phenomena Over Common Engineering Substrates

The surface free energy (SFE) of engineering substrates and the surface tension (ST) of lubricants are known to influence wetting behavior at the interface of the mating mechanical components. The influence of cyclic moieties and heteroatoms in modulating wetting behavior and consequent tribological properties like friction and wear is less well elucidated. Continuing our exploration of “triangle esters” distinguished by the introduction of three-membered heteroatom rings in otherwise commonly used lubricant structures, we demonstrate that friction and wear properties for each ester over a set four different metallic engineering substrates—aluminum, brass, phosphor bronze, and stainless steel—under low load conditions can be effectively correlated with surface properties for the coefficient of friction, and with both surface properties and substrate hardness for wear parameters. The experimentally determined regression equations are used to predict these properties for a fifth substrate, gun metal. The difference in polarity fraction between the substrate and the lubricant is found to have a surprisingly significant influence on wear properties.

WIELAND B44

Abstract Wieland B44 is a multi-alloy phosphor bronze containing 4% tin, 4% zinc and 4% lead. This makes it possible to achieve high mechanical strength and good spring properties. Wieland B44 exhibits excellent wear and corrosion resistance. It has good cold working and excellent machining properties. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance and wear resistance as well as heat treating and machining. Filing Code: Cu-933. Producer or source: Wieland-Werke AG.