Polyamide 6 Microfiber Reinforced Porous Polyurethane Composites

Polyamide 6 ◽

Optical Microscope ◽

Polyurethane Composites ◽

The effect of polyamide 6 (PA6) microfiber and porous polyurethane (PU) on tensile strength and softness of the PA6 microfiber reinforced porous PU composites was investigated. The tensile strength to break the composites is close to that of the corresponding PA6 microfiber nonwovens. It indicates that the PA6 microfiber provides the tensile strength for the composites. The porous PU has little effect on the tensile strength of the composites. The softness of the composites is dependent on PU modulus, which decreases with increasing the PU modulus. In this work, optical microscope and scanning electron microscope (SEM) were used to study the morphology of the composites. The micrographs showed that the diameters of the PA6 microfibers and bubble holes are relatively uniform which are in the range of about 1 to 3 μm.

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

Effect of polyamide 6 on the mechanical behavior of thermoplastic polyurethanes/polyamide 6 blends

10.1177/09544054211040625 ◽

2021 ◽

pp. 095440542110406

Author(s):

Nga Thi-Hong Pham

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Electron Microscope ◽

Mechanical Behavior ◽

Thermoplastic Polyurethane ◽

Polyamide 6 ◽

Thermoplastic Polyurethanes ◽

Microscope Images ◽

Ductility and tensile strength are among the basic mechanical properties of polymers. Generally, it is difficult to enhance the ductility without significantly reducing the tensile strength. In this study, thermoplastic polyurethane (TPU) is mixed with 0%, 2.5%, 5%, 7.5%, 10%, and 12.5% polyamide 6 (PA6). The results show that the sample containing 100% TPU has the largest elongation of 690.5%. When PA6 is added, the elongation decreases gradually to 635.0%, 623.1%, 529.5%, 476.0%, 391.3%, and 242.8%, corresponding to 2.5%, 5%, 7.5%, 10%, 12.5%, and 100% PA6, respectively. The tensile strengths are 36.7, 33.8, 29.4, 26.5, 23.1, and 24.9 MPa, corresponding to 0%, 2.5%, 5%, 7.5%, 10%, and 12.5% PA6 samples, respectively. The tensile strength decreases gradually when the PA6 content is increased. Notably, the tensile strength of the 12.5% PA6 sample increases compared to the 10% PA6 sample. In addition, the hardness of the TPU/PA blend increases slightly as the PA6 ratio is increased. Finally, scanning electron microscope images demonstrate that PA6 particles act as particles dispersed or dissolved in TPU/PA blends.

Effect of Casting Overheat and Rolling Temperature on Morphology of Sulfide in 30MnVS Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.457-458.270 ◽

2012 ◽

Vol 457-458 ◽

pp. 270-273

Author(s):

Yi You Tu ◽

Guo Zhong Li

Keyword(s):

Electron Microscope ◽

Continuous Casting ◽

Optical Microscope ◽

Rolling Temperature ◽

Ferrite Content ◽

Continuous Casting Slab ◽

Intragranular Ferrite ◽

Sulfide Segregation ◽

Effect of superheat and initial rolling temperature on the morphology and distribution of sulfide in non quenched and tempered free cutting steel 30MnVS has been studied by optical microscope and scanning electron microscope. Results show that proper superheat and initial rolling temperature can turn rod-shaped sulfide into massive or globular sulfide，to alleviate sulfide segregation and pro-eutectoid ferrite distribution along the boundary of pearlite clusters in 30MnVS , increase the intragranular ferrite content and optimize the structure of continuous casting slab.

Analysis of an Axle Failure under Torsional Load

Materials Science Forum ◽

10.4028/www.scientific.net/msf.850.101 ◽

2016 ◽

Vol 850 ◽

pp. 101-106 ◽

Cited By ~ 1

Author(s):

Shu Mei Li ◽

Jian Jun Yang ◽

Wei Dong Zhang ◽

August Chang ◽

Cai Xia Zhang ◽

...

Keyword(s):

Electron Microscope ◽

Failure Mechanism ◽

Field Testing ◽

Optical Microscope ◽

Fatigue Lifetime ◽

Torsional Load ◽

Torsional Fatigue ◽

Secondary Cracks ◽

Premature fracture of an axle under torsional load occurred after a tracked military tank had experienced field testing for only 80 kilometers. Visual metallographic examinations were performed with optical microscope (OM) and scanning electron microscope (SEM). The investigation demonstrates that the premature fracture is caused by metallurgical problems inside the axle where the primary and secondary cracks originate, propagate, and eventually result in final catastrophic rupture through torsional fatigue. The failure mechanism is summarized and improvement of the fatigue lifetime for the axle is recommended.

4349242 Specimen observation apparatus including an optical microscope and a scanning electron microscope

Micron and Microscopica Acta ◽

10.1016/0047-7206(83)90082-1 ◽

1983 ◽

Vol 14 (3) ◽

pp. 290

Keyword(s):

Electron Microscope ◽

Optical Microscope ◽

Investigation on the Microstructure Hardness for the Hot Compressed Duplex Steel

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.905.30 ◽

2022 ◽

Vol 905 ◽

pp. 30-37

Author(s):

Shu Lan Zhang ◽

Xiao Dan Zhang ◽

Hai Feng Xu ◽

Chang Wang

Keyword(s):

Electron Microscope ◽

Optical Microscope ◽

Ferrite Phase ◽

Ferrite Formation ◽

Average Hardness ◽

Duplex Steel ◽

Quench Temperature ◽

Fluctuation Range ◽

Effect of microstructure size and type on the hardness for the duplex steel were disclosed by using of optical microscope (OM), scanning electron microscope (SEM) and nanoindenter for the samples hot compressed under different temperature with reduction of 10%, 30%, 50% and 70%. OM and SEM were used to measure the average martensite lamellar width, space and indenter morphology. nanoindenter test characterized the microstructure hardness for the samples under different process. Experiment results show that martensite hardness for the sample hot compressed at 950°C has larger diversity than that of sample hot compressed at 1200°C. The martensite hardness fluctuation range for the sample compressed at 950°C is almost from about 7GPa to 12GPa, while, for the sample compressed at 1200°C, the fluctuation range is basically from about 9GPa to 12GPa. However, the average hardness for the samples hot compressed at 950°C is comparably smaller, which is related with lower quench temperature. The larger martensite hardness fluctuation is mainly related with induced ferrite formation and finer martensite lamellar width. For the ferrite phase, the hardness fluctuation range is lower.

CHARACTERISATION OF BIOMEDICAL TITANIUM LAYERS DEPOSITED BY A VACUUM PLASMA SPRAY PROCESS

Materiali in tehnologije ◽

10.17222/mit.2020.135 ◽

2021 ◽

Vol 55 (2) ◽

pp. 231-235

Author(s):

Mihailo Mrdak ◽

Darko Bajić ◽

Darko Veljić ◽

Marko Rakin

Keyword(s):

Electron Microscope ◽

Hardness Test ◽

Optical Microscope ◽

Mechanical Tests ◽

Test Method ◽

Bonding Layer ◽

Vacuum Plasma Spray ◽

Porous Ti ◽

In this paper we will describe the process of the deposition of thick layers of VPS-Ti coating, which is used as a bonding layer for the upper porous Ti coatings on implant substrates. In order to deposit the powder, we used HÖGANÄS Ti powder labelled as AMPERIT 154.086 -63 µm. In order to test the mechanical properties and microstructure of the VPS-Ti coating, the powder was deposited on Č.4171 (X15Cr13 EN10027) steel substrates. Mechanical tests of the microhardness of the coating were performed by the Vickers hardness test method (HV0.3) and tensile strength by measuring the force per unit area (MPa). The microhardness of the coating is 159 HV0.3, which is consistent with the microstructure. The coating was found to have a good bond strength of 68 MPa. The morphology of the powder particles was examined on a scanning electron microscope. The microstructure of the coating, both when deposited and etched, was examined with an optical microscope and a scanning electron microscope. By etching the coating layers, it was found that the structure is homogeneous and that it consists of a mixture of low-temperature and high-temperature titanium phases (α-Ti + β-Ti). Our tests have shown that the deposited layers of Ti coating can be used as a bonding layer for porous Ti coatings in the production of implants.

Splitting of Islands-in-the-Sea Fibers (PA6/COPET) during Hydroentangling of Nonwovens

Journal of Engineered Fibers and Fabrics ◽

10.1177/155892500700200402 ◽

2007 ◽

Vol 2 (4) ◽

pp. 155892500700200 ◽

Cited By ~ 1

Author(s):

Mbwana Suleiman Ndaro ◽

Xiang-yu Jin ◽

Ting Chen ◽

Chong-wen Yu

Keyword(s):

Tensile Strength ◽

Electron Microscope ◽

Water Jet ◽

Elongation At Break ◽

Sem Micrographs ◽

Fiber Splitting ◽

Data Analyses ◽

This paper summarizes the investigations of hydroentangled islands-in-the-sea (PA6/COPET) fiber webs. An increase in water jet pressure improved the tensile strength and fiber splitting while elongation at break decreased. Scanning Electron Microscope (SEM) micrographs and ANOVA (MS Excel ™) were used for characterizing fiber splitting and data analyses respectively. It can be concluded that with a new innovation in spinnerette design and modification of co-polyester structure, PA6/COPET, fibers can be split in the hydroentanglement process without dissolution of the sea component.

Clouding of Pressed Potassium Bromide Powder

Applied Spectroscopy ◽

10.1366/000370272774352236 ◽

1972 ◽

Vol 26 (2) ◽

pp. 247-251 ◽

Cited By ~ 8

Author(s):

William P. Norris ◽

Allen L. Olsen ◽

Richard G. Brophy

Keyword(s):

Electron Microscope ◽

Adsorbed Water ◽

Optical Microscope ◽

Potassium Bromide ◽

Monomolecular Layer ◽

Cloudy Region ◽

Weak Zones ◽

Ground Powder ◽

The monomolecular layer of water adsorbed on KBr particles is responsible for clouding of disks pressed from finely ground powder. Cloudiness is caused by formation of a multitude of cracks in the disk. The initial cracking can be observed with a low power optical microscope and the extensive cracking in the fully cloudy region is observable with a scanning electron microscope. It is suggested that adsorbed water promotes recrystallization, generating weak zones in the workhardened, elastically stressed disk which fails by cracking.

Study of Microstructure and Mechanical Properties of Extrued Spray Forming Al-8.5Fe-1.3V-1.7Si Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.750-752.671 ◽

2013 ◽

Vol 750-752 ◽

pp. 671-674

Author(s):

Rong Hua Zhang ◽

Yong An Zhang ◽

Bao Hong Zhu

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Electron Microscope ◽

Yield Strength ◽

Room Temperature ◽

Extrusion Process ◽

Spray Forming ◽

Microstructure And Mechanical Properties ◽

In this paper, the Al-8.5Fe-1.3V-1.7Si alloys were fabricated by spray forming and extrusion process. The microstructure and mechanical properties of the alloy were investigated by means of metallographic, scanning electron microscope and tensile test. The results indicate that the tensile strength of the extrued alloys can reach 353MPa, the yield strength 300MPa, elongation 19.12%, at room temperature. At 250°C, the tensile strength of the extrued alloys can reach 221MPa, the yield strength 208MPa, elongation 13.33%.

Influence of prophylaxis on the microleakage of sealants: in vitro study

Journal of Clinical Pediatric Dentistry ◽

10.17796/jcpd.26.4.v8lm755w4n414113 ◽

2002 ◽

Vol 26 (4) ◽

pp. 371-375 ◽

Cited By ~ 1

Author(s):

Ana Beatriz Alonso Chevitarese ◽

Orlando Chevitarese ◽

Ivete Pomarico Ribeiro de Souza ◽

Roberto Braga de Carvalho Vianna

Keyword(s):

Electron Microscope ◽

In Vitro Study ◽

Optical Microscope ◽

Vitro Study ◽

Significant Difference ◽

Group A ◽

Group B ◽

The aim of this study was to evaluate the influence of prophylaxis on the sealants microleakage in 30 premolars divided into: Group A, Group B and Group C. The teeth were analyzed using the optical microscope (OM) and at scanning electron microscope (SEM). There was a statitical significant difference among the groups regarding the presence of microleakage, but not with the presence of tags.