Highly Molybdenum-Alloyed Materials Hastelloy BC-1 (2.4708) and B3 (2.4600): Diffusion Bonding Experiments and Evaluation of Both Mechanical Behavior and Corrosion Resistance in Hot 70 % Sulfuric Acid

Sulphuric acid is a widely used raw material in the chemical industry. Its corrosive effect on materials varies considerably, depending on impurities, temperature and water content. Accordingly, good corrosion resistance under all conditions is very difficult to achieve. This is especially an issue for micro process apparatus with very thin walls. Furthermore, such devices are often joint by diffusion bonding what may alter materials properties due to high temperatures and long dwell times. In fact, for each new material, the diffusion bonding parameters must be optimized and the impact on mechanical as well as corrosion properties must be investigated. In this paper, two high molybdenum alloys, namely Hastelloy B3 and BC-1, were evaluated. Diffusion bonding tests were performed using ten layers of sheet material in between round stock. Corrosion tests were performed in 70 % sulphuric acid at 100°C for 1000 h. Tensile tests on both alloys were carried out for different material conditions, to determine the change in mechanical strength and elongation at fracture values. In general, independent of the condition of the materials, the fracture behavior of both alloys was found to be ductile and the specimens show the typical dimple structure, in the case of diffusion bonded samples, interrupted by weak spots or rather non-bonded areas. These areas are obviously causing the onset of material failure and thus, a degradation of mechanical properties. Tensile samples, that were aged in 70% sulphuric acid at 100°C for 1000 hours showed local corrosion attacks at the grain boundaries at the circumferential surfaces and especially at the joining planes – for Hastelloy B3 much more pronounced than for Hastelloy BC-1. Accordingly, a further decrease of both, the stress- and elongation at fracture values is observed. However, the typical material parameters like 0.2 % yield strength used for dimensioning components are found to be sufficient high, even when operating the materials under such harsh conditions. When concluding the results, at least Hastelloy BC-1 reveals both sufficient good mechanical properties and an excellent corrosion resistance, regardless of the heat treatment, and could be considered for manufacturing micro-process engineering apparatuses operated in a sulphuric acid environment. This is a significant advance compared to the results obtained within a AiF project, previously carried out on four different materials to investigate the corrosion resistance in sulphuric acid.

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Highly Molybdenum-Alloyed Materials Hastelloy BC-1 (2.4708) and B3 (2.4600): Diffusion Bonding Experiments and Evaluation of both Mechanical Behavior and Corrosion Resistance in Hot 70% Sulfuric Acid

Metals ◽

10.3390/met10030376 ◽

2020 ◽

Vol 10 (3) ◽

pp. 376

Author(s):

Thomas Gietzelt ◽

Mario Walter ◽

Volker Toth ◽

Florian Messerschmidt ◽

Ralf Dahm

Keyword(s):

Mechanical Properties ◽

Corrosion Resistance ◽

Sulfuric Acid ◽

Diffusion Bonding ◽

Tensile Tests ◽

Raw Material ◽

Significant Advance ◽

Thin Walls ◽

Corrosive Effect ◽

Material Conditions

Sulfuric acid is a widely used raw material in the chemical industry. Its corrosive effect on materials varies considerably, depending on impurities, temperature and water content. This is an issue for micro process apparatuses with thin walls. Such devices are often joint by diffusion bonding what may alter materials properties due to high temperatures and long dwell times. In this paper, two high molybdenum alloys, namely Hastelloy B3 and BC-1, were investigated. Diffusion bonding tests were performed at different temperatures. Tensile tests were carried out for different material conditions, to determine the change in mechanical strength and elongation at fracture values. The fracture behavior of both alloys was ductile and the fracture surfaces showed dimple structure. For diffusion bonded samples, weak spots or rather non-bonded areas were found. These obviously caused the onset of material failure and thus, degradation of mechanical properties. Tensile samples, aged in 70% sulfuric acid at 100 °C for 1000 h showed local corrosion attacks at the grain boundaries at the circumferential surfaces and joining planes—for Hastelloy B3 more pronounced than for Hastelloy BC-1. Accordingly, a further decrease of stress and elongation at fracture values was observed. However, 0.2% yield strength used for dimensioning components are found to be reasonable. As conclusion, at least Hastelloy BC-1 reveals both good mechanical properties and an excellent corrosion resistance, regardless of the heat treatment. This is a significant advance compared to the results obtained from a previously research project on four different alloys.

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Development of Al–Mg–Si alloy performance by addition of grain refiner Al–5Ti–1B alloy

Science Progress ◽

10.1177/00368504211029469 ◽

2021 ◽

Vol 104 (2) ◽

pp. 003685042110294

Author(s):

Khaled Abd El-Aziz ◽

Emad M Ahmed ◽

Abdulaziz H Alghtani ◽

Bassem F Felemban ◽

Hafiz T Ali ◽

...

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Corrosion Resistance ◽

Testing Machine ◽

Dendritic Structure ◽

Grain Refiner ◽

Corrosion Properties ◽

Average Grain Size ◽

Structural Applications ◽

Alloy Addition

Aluminum alloys are the most essential part of all shaped castings manufactured, mainly in the automotive, food industry, and structural applications. There is little consensus as to the precise relationship between grain size after grain refinement and corrosion resistance; conflicting conclusions have been published showing that reduced grain size can decrease or increase corrosion resistance. The effect of Al–5Ti–1B grain refiner (GR alloy) with different percentages on the mechanical properties and corrosion behavior of Aluminum-magnesium-silicon alloy (Al–Mg–Si) was studied. The average grain size is determined according to the E112ASTM standard. The compressive test specimens were made as per ASTM: E8/E8M-16 standard to get their compressive properties. The bulk hardness using Vickers hardness testing machine at a load of 50 g. Electrochemical corrosion tests were carried out in 3.5 % NaCl solution using Autolab Potentiostat/Galvanostat (PGSTAT 30).The grain size of the Al–Mg–Si alloy was reduced from 82 to 46 µm by the addition of GR alloy. The morphology of α-Al dendrites changes from coarse dendritic structure to fine equiaxed grains due to the addition of GR alloy and segregation of Ti, which controls the growth of primary α-Al. In addition, the mechanical properties of the Al–Mg–Si alloy were improved by GR alloy addition. GR alloy addition to Al–Mg–Si alloy produced fine-grained structure and better hardness and compressive strength. The addition of GR alloy did not reveal any marked improvements in the corrosion properties of Al–Mg–Si alloy.

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Strength Enhancement of Superduplex Stainless Steel Using Thermomechanical Processing

Metals ◽

10.3390/met11071094 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1094

Author(s):

M. A. Lakhdari ◽

F. Krajcarz ◽

J. D. Mithieux ◽

H. P. Van Landeghem ◽

M. Veron

Keyword(s):

Mechanical Properties ◽

Stainless Steel ◽

Thermomechanical Processing ◽

Tensile Tests ◽

Image Correlation ◽

Strength Enhancement ◽

Industrial Material ◽

Superduplex Stainless Steel ◽

The Impact ◽

Strength Improvement

The impact of microstructure evolution on mechanical properties in superduplex stainless steel UNS S32750 (EN 1.4410) was investigated. To this end, different thermomechanical treatments were carried out in order to obtain clearly distinct duplex microstructures. Optical microscopy and scanning electron microscopy, together with texture measurements, were used to characterize the morphology and the preferred orientations of ferrite and austenite in all microstructures. Additionally, the mechanical properties were assessed by tensile tests with digital image correlation. Phase morphology was not found to significantly affect the mechanical properties and neither were phase volume fractions within 13% of the 50/50 ratio. Austenite texture was the same combined Goss/Brass texture regardless of thermomechanical processing, while ferrite texture was mainly described by α-fiber orientations. Ferrite texture and average phase spacing were found to have a notable effect on mechanical properties. One of the original microstructures of superduplex stainless steel obtained here shows a strength improvement by the order of 120 MPa over the industrial material.

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Mechanical Properties of Spruce Wood Extracted from GLT Beams Loaded by Fire

Sustainability ◽

10.3390/su13105494 ◽

2021 ◽

Vol 13 (10) ◽

pp. 5494

Author(s):

Lucie Kucíková ◽

Michal Šejnoha ◽

Tomáš Janda ◽

Jan Sýkora ◽

Pavel Padevět ◽

...

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Cross Section ◽

Negative Impact ◽

Tensile Tests ◽

Thermal Recovery ◽

Bending Test ◽

Small Scale ◽

Spruce Wood ◽

The Impact

Heating wood to high temperature changes either temporarily or permanently its physical properties. This issue is addressed in the present contribution by examining the effect of high temperature on residual mechanical properties of spruce wood, grounding on the results of full-scale fire tests performed on GLT beams. Given these tests, a computational model was developed to provide through-thickness temperature profiles allowing for the estimation of a charring depth on the one hand and on the other hand assigning a particular temperature to each specimen used subsequently in small-scale tensile tests. The measured Young’s moduli and tensile strengths were accompanied by the results from three-point bending test carried out on two groups of beams exposed to fire of a variable duration and differing in the width of the cross-section, b=100 mm (Group 1) and b=160 mm (Group 2). As expected, increasing the fire duration and reducing the initial beam cross-section reduces the residual bending strength. A negative impact of high temperature on residual strength has also been observed from simple tensile tests, although limited to a very narrow layer adjacent to the charring front not even exceeding a typically adopted value of the zero-strength layer d0=7 mm. On the contrary, the impact on stiffness is relatively mild supporting the thermal recovery property of wood.

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

Materials ◽

10.3390/ma13051242 ◽

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.

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Superplastic Forming and Reaction Diffusion Bonding Process of Hollow Structural Component for Mg-Gd-Y-Zn-Zr Rare Earth Magnesium Alloy

Metals ◽

10.3390/met12010152 ◽

2022 ◽

Vol 12 (1) ◽

pp. 152

Author(s):

Peng Peng ◽

Shaosong Jiang ◽

Zhonghuan Qin ◽

Zhen Lu

Keyword(s):

Mechanical Properties ◽

Diffusion Bonding ◽

Structural Component ◽

Bonding Temperature ◽

Reaction Diffusion ◽

Superplastic Forming ◽

Tensile Tests ◽

Interface Roughness ◽

Size Growth ◽

Cu Interlayer

This work fabricated a double hollow structural component of Mg-8.3Gd-2.9Y-0.8Zn-0.2Zr alloy by superplastic forming (SPF) and reaction-diffusion bonding (RDB). The superplastic characteristic and mechanical properties of Mg-8.3Gd-2.9Y-0.8Zn-0.2Zr alloy sheets at 250–450 °C were studied. Tensile tests showed that the maximum elongation of tensile specimens was about 1276.3% at 400 °C under a strain rate of 1 × 10−3 s−1. Besides, the effect of bonding temperature and interface roughness on microstructure and mechanical properties of the reaction diffusion-bonded joints with a Cu interlayer was investigated. With the increase of temperature, the diffusion coefficient of Cu increases, and the diffusion transition region becomes wider, leading to tightening bonding of the joint. However, the bonding quality of the joint will deteriorate due to grain size growth at higher temperatures. Shear tests showed that the highest strength of the joints was 152 MPa (joint efficiency = 98.7%), which was performed at 460 °C.

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Effect of homogenization temperature and soaking time on the microstructure and corrosion properties of a twin roll casted AA3003

CORROSION ◽

10.5006/3813 ◽

2021 ◽

Author(s):

Donovan Verkens ◽

Reynier Revilla ◽

Mert Günyüz ◽

Cemil Işıksaçan ◽

Herman Terryn ◽

...

Keyword(s):

Heat Treatment ◽

Corrosion Resistance ◽

Heat Exchangers ◽

Corrosion Behaviour ◽

Life Time ◽

Homogenization Temperature ◽

Corrosion Properties ◽

Cross Sectional ◽

The Impact ◽

Twin Roll

The AA3003 alloy is widely used as fin material in heat exchangers. The life time of these heat exchangers is mostly determined by their corrosion properties. Twin roll casting (TRC) of AA3003 material is known to often result in the formation of a macrosegregation area of alloying elements towards the centre plane of the casted strip (centre line segregation = CLS). Considering the potential exposure of cross-sectional areas of TRC material in the heat exchanger fin application, and the relatively high corrosion susceptibility of the CLS, the study of this region is of key importance to understand the microstructural effects on the resulting corrosion mechanisms and kinetics for these materials. Typically the alloys are homogenized to bring the microstructures closer to an equilibrium state, but the impact of this heat treatment on the corrosion properties is insufficiently studied. Therefore, this study investigates the effect of different homogenization procedures on the corrosion properties of the CLS and the interaction of the intermetallic particles with the surrounding aluminium matrix. This work shows that the pitting corrosion resistance is greatly dependent on the homogenization temperature, with better corrosion resistance obtained with higher temperature, especially near the CLS. This difference in corrosion behaviour is completely attributed to a difference in microstructure and not to an oxide layer effect. Furthermore, it is observed that not only temperature will have a large influence on the corrosion resistance, but duration of the heat treatment as well.

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Study on Weldablity of Dissimilar Steel between 16MnR and S31803

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.391-392.768 ◽

2011 ◽

Vol 391-392 ◽

pp. 768-772 ◽

Cited By ~ 1

Author(s):

Li Yang ◽

Zhan Zhe Zhang

Keyword(s):

Mechanical Properties ◽

Corrosion Resistance ◽

Impact Toughness ◽

Weld Metal ◽

Welded Joint ◽

Optical Microscope ◽

Dissimilar Steel ◽

Austenite Content ◽

Mechanical Properties And Corrosion ◽

The Impact

The weldablity of dissimilar steel between 16MnR and S31803 was analyzed and researched. By means of optical microscope (OM), the microstructure of the weld joint was investigated, which is welded by tungsten inert gas arc backing welding (GTAW) and manual arc filling welding (SMAW). The mechanical properties and corrosion resistance of the welded joint was also tested and studied. Results indicate that austenite and acicular ferrite distribute uniformly in the weld metal, which strengths the toughness and ductility of the joint. The austenite content in weld is higher than that in over-heated zone of S31803.The SMAW joint structure is coarsening than that of GTAW and has more austenite content. It is also observed that there are a decarburization layer and a carbon-enriched zone nearby the fusion line. And very small amounts of the third phase of harmful metal phase are found in the fusion zone of S31803 side. The welded joint shows the excellent mechanical properties and corrosion resistance. The impact toughness of the weld metal is higher than in HAZ of 16MnR side, and the impact toughness at GTAW side and in HAZ is superior to the SMAW side.

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High Temperature and Corrosion Properties of A Newly Developed Fe-Al-O Based OPH Alloy

Metals ◽

10.3390/met10020167 ◽

2020 ◽

Vol 10 (2) ◽

pp. 167 ◽

Cited By ~ 1

Author(s):

Omid Khalaj ◽

Ehsan Saebnoori ◽

Hana Jirková ◽

Ondřej Chocholatý ◽

Jiří Svoboda

Keyword(s):

Mechanical Properties ◽

Corrosion Resistance ◽

High Temperature ◽

Thermomechanical Properties ◽

Production Costs ◽

Nacl Solution ◽

Corrosion Properties ◽

Ambient Temperatures ◽

The Matrix ◽

Specific Amount

Fe–Al–O-based materials are currently undergoing a great deal of development because of their many special properties. However, lack of strength at high temperatures, limited ductility at ambient temperatures and corrosion resistance have hindered a wider application of these materials. Recently, a new Fe–Al-based oxide precipitation hardened (OPH) steel was developed by the authors to improve the mechanical properties and oxidation resistance. The new OPH alloys are produced by dissolving a specific amount of oxygen in the matrix during mechanical alloying followed by precipitation of fine dispersion of aluminum or yttrium oxides during hot consolidation. A series of tests was performed to evaluate the thermomechanical properties and corrosion resistance in a 3.5% NaCl solution. The results show improved corrosion resistance, as well as mechanical properties, while the production costs of this material are lower than for traditional materials.

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Mechanical Properties for Elephant Dung and its Utilization as a Raw Material Composites Sheet: A Study

Asian Journal of Engineering and Applied Technology ◽

10.51983/ajeat-2021.10.1.2720 ◽

2021 ◽

Vol 10 (1) ◽

pp. 1-7

Author(s):

Rohit Kumar ◽

Ramratan . ◽

Anupam Kumar ◽

Rajinder Singh Smagh

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Impact Strength ◽

Polymer Composite ◽

Natural Fiber ◽

Testing Machine ◽

Raw Material ◽

Weight Percentage ◽

The Impact ◽

Elephant Dung

Elephant dung is an excellent source of cellulosic fiber that is a basic requirement for paper making. But they contributed to very small percentage production of elephant dung. So, researchers are trying to find a new area of utilization of elephant dung fiber pulp as in reinforcement’s polymer composite. In this experiment element dung fiber pulp in the natural fiber component chemically treated with alkaline and soda AQ solution in this study, it has been aimed to use elephant dung fiber pulp in composite material and to study mechanical properties of the produced material. The produced composite samples were then characterized using tensile test, Izod impact test, thickness test. The fracture surface of the polymer composite sample was also inspected with the help of SEM. The content of elephant dung fiber pulp is varied (35%, 45%, 55%) weight percentage whereas the epoxy resin is varied (50%, 40%, 30%) percentage is kept constant 15% in hardener. The entire sample has been tested in a universal testing machine as per ASTM standard for tensile strength and impact strength. It is observed that composite with 35% fiber pulp is having the highest tensile strength of 4mm 6.445 Mpa and 8mm 11.80 Mpa. The impact strength of composite with 35% fiber pulp washes highest than 45% to 55% dung fiber pulp. This produces composite sheet will be used for the surfboards, sporting goods, building panel this not only reduces the cost but also save from environmental pollution.

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