Effects of ultrasonic surface rolling and plasma nitriding on microstructure and properties of 690TT alloy

2022 ◽  
Author(s):  
Baoquan Chen ◽  
Junbiao Liu ◽  
xiaoxian li ◽  
Weiqing Chen ◽  
xuehui zhang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Sea Water ◽  
Plasma Nitriding ◽  
Corrosion Performance ◽  
Untreated Sample ◽  
Cross Sectional ◽  
Hardness Tester ◽  
Tensile Tester ◽  
Treated Sample ◽  
Pre Treatment

Abstract To enhance surface mechanical properties of 690TT alloy, a surface hardening layer was obtained by ultrasonic surface rolling treatment (USRT) and plasma nitriding (PN). The surface morphology, mechanical properties, wear performances and corrosion performance were investigated by XRD, TEM, using a hardness tester, tensile tester, wear tester and electrochemical workstation in simulated sea water, respectively. The results showed that USRT as the pre-treatment can strengthen the performance of PN treatment samples. The USRT+PN treated sample showed existence of dislocation tangles and twin grains. Corrosion resistance in simulated sea water was enhanced. The surface microhardness increased by 180 % compared with the untreated sample, the cross-sectional hardness gradually decreased till the depth of 1mm. The tensile strength increased by a factor of 90% while the elongation decreased by only 40%. The wear scar was narrower and shallower than the untreated sample and the wear rate was significantly dropped. This paper aims at providing a new method for surface strengthening of 690TT alloy.

A comparative study on the mechanical behaviors of surface-strengthened Nitinol 60 alloy and steel

2019 ◽  
Vol 43 (4) ◽  
pp. 569-578
Author(s):  
Qunfeng Zeng
Keyword(s):  
Mechanical Properties ◽  
Wear Mechanism ◽  
Adhesive Wear ◽  
Engineering Application ◽  
High Hardness ◽  
Hardened Layer ◽  
Untreated Sample ◽  
Treated Sample ◽  
Before And After ◽  
The Coefficient Of Friction

Nitinol 60 alloy and steel were treated using supersonic fine-particle bombardment (SFPB) to improve their mechanical properties. The formation of the strengthened layer and the mechanical properties including surface roughness, hardness, and tribological properties of the untreated and treated samples were systematically investigated using surface profiler, micro-Vickers hardness, and ball-on-disk tribometer, respectively. The influences of SFPB treatment on the mechanical properties of samples are discussed. The results show that a hardened layer is formed on samples after SFPB treatment and that the treated samples exhibit high hardness and good wear resistance. It is also found that the coefficient of friction (CoF) of Nitinol 60 alloy is lowest among all the samples before and after surface treatment. The wear mechanism of the untreated sample is adhesive wear; however, the wear mechanism of the treated sample is adhesive and abrasive wear. This study will provide clear guidelines for the engineering application of Nitinol 60 alloy.

scholarly journals Effects of the Prefabricated Cu-Ti Film on the Microstructure and Mechanical Properties of the Multiphase Coating by Thermo Plasma Nitriding on C17200 Cu Alloy

Coatings ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 694
Author(s):  
Yandan Zhu ◽  
Mufu Yan ◽  
Quanli Zhang ◽  
Qiwen Wang ◽  
Hangyu Zhuo
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Plasma Nitriding ◽  
Surface Hardness ◽  
Cross Sectional ◽  
Cu Alloy ◽  
Cu Substrates ◽  
Modified Surface ◽  
N Compounds ◽  
Ti Films

To improve the surface wear resistance, plasma nitriding of the prefabricated Cu-Ti films on the C17200 Cu alloy is performed to investigate the effects of the composition of the Cu-Ti films on the microstructure and the mechanical properties of the modified surface. The results firstly showed that obvious microstructure evolution appeared during the thermo-plasma nitriding process, where both the surface morphology of the composed phases and the cross-sectional profiles of the multiphase coatings varied for the three types of films. Small amounts of Ti-N compounds, Be3Ti2Cu, and different types of Cu-Ti intermetallics formed in the multiphase coating after plasma nitriding, which is dependent on the composition of the prefabricated Cu-Ti film. Correspondingly, the surface hardness and the wear resistance of the C17200 Cu substrates were obviously improved, with the obtained adhesive strength of the substrate reaching a satisfactory range.

MECHANICAL PROPERTIES OF THE Fe-Al-Nb COATING BY DOUBLE GLOW PLASMA SURFACE METALLURGY

2018 ◽  
Vol 25 (08) ◽  
pp. 1950034 ◽  
Author(s):  
ZELEI ZHANG ◽  
ZHENGJUN YAO
Keyword(s):  
Mechanical Properties ◽  
Elastic Modulus ◽  
Sliding Friction ◽  
Cross Sectional ◽  
Plasma Surface ◽  
Q235 Steel ◽  
Treated Sample ◽  
Modification Technique ◽  
Friction Performance ◽  
Glow Plasma

The Q235 steel was covered by Fe–Al–Nb alloyed coating to improve the mechanical properties of the Q235 steel. This double glow plasma surface metallurgy (DGPSM) surface modification technique was carried out at 1023[Formula: see text]K and pressure of 38[Formula: see text]Pa for 4.5[Formula: see text]h. The surface morphology represented the typical Volmer–Weber mode, an island structure which was accumulated by numerous small particles, and most of the angles formed between three islands were about 120[Formula: see text] where there was no appreciable defect. Meanwhile, in the cross-sectional morphology of the Fe–Al–Nb coating, there was a deposition layer, a diffusion layer and two transition regions between the different adjacent interfaces, and the coating approximate 17[Formula: see text][Formula: see text]m was found to be metallurgically adhered to the Q235 steel. The basic mechanical properties of the Fe–Al–Nb coating and Q235 steel including the hardness, elastic modulus and friction performance were measured and compared. The results showed that the formation of Fe3Al, FeAl, and Fe2Nb intermetallic compounds and Nb carbides in the coating can enhance the mechanical properties of the treated sample. The nanoindentation tests indicated that the hardness and elastic modulus of Fe–Al–Nb coating were 8.08[Formula: see text]GPa and 260.03[Formula: see text]GPa which were much higher than Q235 steel. The sliding friction tests showed that Fe–Al–Nb coating significantly improved the friction performance of Q235 steel at the speed of 300, 600 and 900[Formula: see text]rpm with load 320[Formula: see text]g for 15[Formula: see text]min.

scholarly journals Temperature Dependence on Tensile Mechanical Properties of Sintered Silver Film

Materials ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4061
Author(s):  
Keisuke Wakamoto ◽  
Yo Mochizuki ◽  
Takukazu Otsuka ◽  
Ken Nakahara ◽  
Takahiro Namazu
Keyword(s):  
Mechanical Properties ◽  
Uniaxial Tensile ◽  
Sem Images ◽  
Cross Sectional ◽  
Reliability Design ◽  
Brittle Ductile Transition ◽  
Tensile Tester ◽  
Influence Of Temperature On ◽  
Ductile Behavior ◽  
Sintered Silver

This paper investigates the influence of temperature on tensile mechanical properties of sintered silver (s-Ag) films with 8–10 μm in thickness for fundamental reliability design of semiconductor systems. The s-Ag film sintered under a pressure of 60 MPa possesses the porosity (p) around 5% determined from cross-sectional scanning electron microscope (SEM) images. The stress–strain (S-S) curves of s-Ag and pure silver (p-Ag) films are obtained using originally designed uniaxial tensile tester at temperatures from 25 °C to 150 °C. The S-S curves of p-Ag indicate ductile behavior irrespective of temperature, whereas those of s-Ag indicate brittle-ductile transition at 120 °C. Compared with p-Ag, s-Ag possesses low Young’s modulus (E) and high ultimate tensile strength (UTS) below 80 °C. The mechanism of brittle-ductile transition is discussed based on fracture surface observation results.

Effect of silver nitrate on some mechanical properties of heat polymerizing acrylic resins

2019 ◽  
Vol 14 (1) ◽  
pp. 110
Author(s):  
Assiss. Prof. Dr. Sabiha Mahdi Mahdi ◽  
Dr. Firas Abd K. Abd K.
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Silver Nitrate ◽  
Surface Hardness ◽  
Mechanical Tests ◽  
Hardness Tester ◽  
Acrylic Resins ◽  
The Difference

Aim: The aimed study was to evaluate the influence of silver nitrate on surfacehardness and tensile strength of acrylic resins.Materials and methods: A total of 60 specimens were made from heat polymerizingresins. Two mechanical tests were utilized (surface hardness and tensile strength)and 4 experimental groups according to the concentration of silver nitrate used.The specimens without the use of silver nitrate were considered as control. Fortensile strength, all specimens were subjected to force till fracture. For surfacehardness, the specimens were tested via a durometer hardness tester. Allspecimens data were analyzed via ANOVA and Tukey tests.Results: The addition of silver nitrate to acrylic resins reduced significantly thetensile strength. Statistically, highly significant differences were found among allgroups (P≤0.001). Also, the difference between control and experimental groupswas highly significant (P≤0.001). For surface hardness, the silver nitrate improvedthe surface hardness of acrylics. Highly significant differences were statisticallyobserved between control and 900 ppm group (P≤0.001); and among all groups(P≤0.001)with exception that no significant differences between control and150ppm; and between 150ppm and 900ppm groups(P>0.05).Conclusion: The addition of silver nitrate to acrylics reduced significantly the tensilestrength and improved slightly the surface hardness.

COASTAL AND ESTUARINE SEDIMENT DYNAMICS IN THE MEZEN BAY AND ESTUARIES MEZEN AND KULOY

2018 ◽  
Author(s):  
Н. Демиденко ◽  
N. Demidenko
Keyword(s):  
River Water ◽  
River Discharge ◽  
Sea Water ◽  
Sediment Dynamics ◽  
Estuarine Sediment ◽  
Sea Surface ◽  
Cross Sectional ◽  
Sand Waves ◽  
Tidal Estuaries ◽  
High Concentrations

In the Mezen bay and estuaries Mezen and Kuloy can be high concentrations of mud suspension there, involving the formation at times mobile suspensions and settled mud. Within estuaries the river water is mixed with the sea water by the action of tidal motions, by waves on the sea surface and by the river discharge forcing its way to the sea. Nearly all shallow tidal estuaries, where currents exceed about 1,0m s-1 and where sand is present, have sand waves. Sand waves have a variety of cross-sectional and plan forms.

scholarly journals Effect of Multiple Reflows on the Interfacial Reactions and Mechanical Properties of an Sn-0.5Cu-Al(Si) Solder and a Cu Substrate

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2367
Author(s):  
Junhyuk Son ◽  
Dong-Yurl Yu ◽  
Yun-Chan Kim ◽  
Shin-Il Kim ◽  
Min-Su Kim ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
High Heat ◽  
Interfacial Reactions ◽  
Future Application ◽  
Scanning Calorimetry ◽  
Cross Sectional ◽  
Automotive Electronic ◽  
Transmission Electron ◽  
Si Content ◽  
Lead Free Solders

In this study, the interfacial reactions and mechanical properties of solder joints after multiple reflows were observed to evaluate the applicability of the developed materials for high-temperature soldering for automotive electronic components. The microstructural changes and mechanical properties of Sn-Cu solders regarding Al(Si) addition and the number of reflows were investigated to determine their reliability under high heat and strong vibrations. Using differential scanning calorimetry, the melting points were measured to be approximately 227, 230, and 231 °C for the SC07 solder, SC-0.01Al(Si), and SC-0.03Al(Si), respectively. The cross-sectional analysis results showed that the total intermetallic compounds (IMCs) of the SC-0.03Al(Si) solder grew the least after the as-reflow, as well as after 10 reflows. Electron probe microanalysis and transmission electron microscopy revealed that the Al-Cu and Cu-Al-Sn IMCs were present inside the solders, and their amounts increased with increasing Al(Si) content. In addition, the Cu6Sn5 IMCs inside the solder became more finely distributed with increasing Al(Si) content. The Sn-0.5Cu-0.03Al(Si) solder exhibited the highest shear strength at the beginning and after 10 reflows, and ductile fracturing was observed in all three solders. This study will facilitate the future application of lead-free solders, such as an Sn-Cu-Al(Si) solder, in automotive electrical components.

scholarly journals Mechanical, Thermal and Rheological Properties of Polyethylene-Based Composites Filled with Micrometric Aluminum Powder

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1242
Author(s):  
Olga Mysiukiewicz ◽  
Paulina Kosmela ◽  
Mateusz Barczewski ◽  
Aleksander Hejna
Keyword(s):  
Mechanical Properties ◽  
Melt Flow Index ◽  
Tensile Tests ◽  
Mechanical Analysis ◽  
Flow Index ◽  
Scanning Calorimetry ◽  
Metal Composites ◽  
Pre Treatment ◽  
The Impact ◽  
Properties Of Composites

Investigations related to polymer/metal composites are often limited to the analysis of the electrical and thermal conductivity of the materials. The presented study aims to analyze the impact of aluminum (Al) filler content (from 1 to 20 wt%) on the rarely investigated properties of composites based on the high-density polyethylene (HDPE) matrix. The crystalline structure, rheological (melt flow index and oscillatory rheometry), thermal (differential scanning calorimetry), as well as static (tensile tests, hardness, rebound resilience) and dynamic (dynamical mechanical analysis) mechanical properties of composites were investigated. The incorporation of 1 and 2 wt% of aluminum filler resulted in small enhancements of mechanical properties, while loadings of 5 and 10 wt% provided materials with a similar performance to neat HDPE. Such results were supported by the lack of disturbances in the rheological behavior of composites. The presented results indicate that a significant content of aluminum filler may be introduced into the HDPE matrix without additional pre-treatment and does not cause the deterioration of composites’ performance, which should be considered beneficial when engineering PE/metal composites.

scholarly journals Patient-reported experience and outcomes from orthodontic treatment

2020 ◽  
Vol 47 (2) ◽  
pp. 107-115
Author(s):  
Elizabeth Bradley ◽  
Andrew Shelton ◽  
Trevor Hodge ◽  
David Morris ◽  
Hilary Bekker ◽  
...  
Keyword(s):  
Secondary Care ◽  
Orthodontic Treatment ◽  
Clinical Care ◽  
Patient Treatment ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Fixed Appliance ◽  
Treatment Experience ◽  
Patient Reported ◽  
Pre Treatment

Objective: To measure patient-reported impact of orthodontic treatment in terms of pre-treatment concerns, treatment experience and treatment outcome. Setting: Four sites in Yorkshire, including two secondary care settings (Leeds Dental Institute and St Luke’s Hospital, Bradford) and two specialist orthodontic practices. Design: Cross-sectional survey. Participants: NHS orthodontic patients (aged 12+ years) who have completed comprehensive orthodontic treatment, excluding orthognathic surgery and craniofacial anomalies. Methods: Participants were opportunistically identified by the direct clinical care team during scheduled appointments and those eligible were invited to participate. Data were collected using the Orthodontic Patient Treatment Impact Questionnaire (OPTIQ), a validated 12-item measure with questions relating to pre-treatment experience, impact of treatment and outcome from treatment. Results: Completed questionnaires for analysis included 120 from primary care and 83 from secondary care. The most common pre-treatment concerns were alignment (89%) and being embarrassed to smile (63%). The most common expectations from orthodontic treatment were improved confidence to eat (87%) and smile (72%) in front of others, improved appearance of teeth (85%) and reduced teasing/bullying (63%). Only 67% respondents recalled receiving written information and the lowest recall related to retainer type and length of retention. The most commonly reported complications were sore mouth (68%), fixed appliance breakage (61%) and gingivitis (39%). Treatment caused greatest impact in relation to pain, limitations in eating and effect on speech. Overall satisfaction with orthodontic treatment was reported by 96% of respondents, 87% would have orthodontic treatment again (if needed) and 91% would recommend treatment to a friend. Conclusions: The OPTIQ is a useful patient-reported tool to identify pre-treatment concerns and expectations, treatment experience and outcome. Orthodontic treatment leads to high levels of satisfaction.

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