Small Additions Of Boron Research Articles

Microstructure and Properties Variation of High-Performance Grey Cast Iron via Small Boron Additions

A study was undertaken to investigate the effects of small boron additions on the solidification and microstructure of hypo-eutectic alloyed grey cast iron. The characteristic temperatures upon crystallisation of the treated metal melt were recorded, specifically those concerning small boron addition by using thermal analysis with the ATAS system. Additionally, a standardised wedge test was set to observe any changes in chill performance. The microstructures of thermal analysis samples were analysed using a light optical microscope (LOM) and field emission scanning electron microscopy (FE-SEM) equipped with energy dispersive spectroscopy (EDS), which reveal variations in graphite count number with the addition of boron within observed random and undercooled flake graphite. The effect of boron was estimated by the classical analytical and statistical approach. The solidification behaviour under equilibrium conditions was predicted by a thermodynamic approach using Thermo-Calc. Based on all gathered data, a response model was set with boron for given melt quality and melt treatment using the experimentally determined data. The study reveals that boron as a ferrite and carbide-promoting element under the experimental set shows weak nucleation potential in synergy with other heterogenic nuclei at increased solidification rates, but no considerable changes were observed by the TA samples solidified at slower cooling rates, indicating the loss of the overall inoculation effect. The potential presence of boron nitride as an inoculator for graphite precipitation for a given melt composition and melt treatment was not confirmed in this study. It seems that boron at increased solidification rates can contribute to overall inoculation, but at slower cooling rates these effects are gradually lost. In the last solidification range, an increased boron content could have a carbide forming nature, as is usually expected. The study suggests that boron in traces could affect the microstructure and properties of hypo-eutectic alloyed grey cast iron.

Influence of silicon, boron and rare-earth metals on corrosion resistance of austenitic chromium-nickel steel

The effect of silicon (in range 0.14 – 0.78 wt. %), boron, and rare-earth metals (REM) on the corrosion resistance of low-carbon austenitic chromium-nickel steel of 03Kh18N11 (AISI 304L) grade was studied. It is shown that all steels in quenched state when tested in boiling 56 and 65 % HNO3 solutions have comparable corrosion rates, which do not exceed the critical norm (0.5 mm/year) in accordance with GOST 6032 – 2017 (State Standard). Testing samples in boiling 27 % HNO3 + 4 g/l Cr+6 solution are susceptible to intergranular corrosion (IGC). The corrosion rate and the penetration depth of IGC increase with increasing silicon concentration from 0.14 to 0.78 wt. %. Study of the effect of nitric acid concentration and test temperature has shown that steel with 0.78 wt. % Si has significant corrosion losses exceeding the critical ones when testing in 56 and 65 % HNO3 solutions with temperature of 120 and 130 °С. But steel with high silicon content (0.78 wt. %) and low carbon concentration (0.020 – 0.022 %) after quenching in a range of 1080 – 1150 °C and tempering at 650 °C does not exceed the critical norm on average corrosion rate. Only 0.01 wt. % increase in carbon concentration leads to a significant (more than 30 times) increase in corrosion rate of sensitized steel. It is shown that microalloying with REM does not impair corrosion resistance of sensitized steel. In contrast to REM, alloying chromium-nickel steel with even a small addition of boron (0.0015 %) reduces steel corrosion resistance by an order of magnitude. Corrosion rate inverse dependence on quenching temperature is observed when, with increasing temperature, corrosion rate of 02Kh18N11GS0.38R steel increases. The effect of silicon (in range 0.14 – 0.78 wt. %), boron, and rare-earth metals (REM) on the corrosion resistance of low-carbon austenitic chromium-nickel steel of 03Kh18N11 (AISI 304L) grade was studied. It is shown that all steels in quenched state when tested in boiling 56 and 65 % HNO3 solutions have comparable corrosion rates, which do not exceed the critical norm (0.5 mm/year) in accordance with GOST 6032 – 2017 (State Standard). Testing samples in boiling 27 % HNO3 + 4 g/l Cr+6 solution are susceptible to intergranular corrosion (IGC). The corrosion rate and the penetration depth of IGC increase with increasing silicon concentration from 0.14 to 0.78 wt. %. Study of the effect of nitric acid concentration and test temperature has shown that steel with 0.78 wt. % Si has significant corrosion losses exceeding the critical ones when testing in 56 and 65 % HNO3 solu tions with temperature of 120 and 130 °С. But steel with high silicon content (0.78 wt. %) and low carbon concentration (0.020 – 0.022 %) after quenching in a range of 1080 – 1150 °C and tempering at 650 °C does not exceed the critical norm on average corrosion rate. Only 0.01 wt. % increase in carbon concentration leads to a significant (more than 30 times) increase in corrosion rate of sensitized steel. It is shown that microalloying with REM does not impair corrosion resistance of sensitized steel. In contrast to REM, alloying chromium-nickel steel with even a small addition of boron (0.0015 %) reduces steel corrosion resistance by an order of magnitude. Corrosion rate inverse dependence on quenching temperature is observed when, with increasing temperature, corrosion rate of 02Kh18N11GS0.38R steel increases.

Impact of addition of manganese and boron carbide on aluminium metal matrix composites using powder metallurgy process

Aluminium boron carbide composite forms an important class of low weight high strength composite that is widely used in aerospace and defence industry. Owing to its high cost and brittleness at high concentrations, use of boron carbide is limited up to certain extent. The main purpose of this study is to maximize the strength of aluminium composites by adding boron carbide & manganese in it by powder metallurgy process to obtain better mechanical properties. As the pure Aluminium has a low tensile strength and is less ductile and it can undergo the deformation easily at low temperatures. Small additions of manganese and boron are used to give strength to the alloy and enhance its mechanical strength and cast ability. Powder metallurgy technique is used to make the composites with better mechanical properties. These composites can replace the Aluminium metal and the practical applications can be made into the automobile industry, aerospace applications and military applications. Optimum weight percentage of Aluminium boron & Manganese were mixed in different proportions to make the cylindrical shape samples to determine their strength these samples were made by mixing the powders at 2% 4% 6% and the strength were compared.

Effect of cooling rate on precipitation behaviour and transformation characteristics of a novel FeCrVBC cast alloy

This work presents the investigation of the solidification and cooling behaviour of a newly developed Fe92.65Cr4.2V2.1B0.05C1 wt% (FeCrVBC) tool steel with special emphasis to phase formations and transformations. JMatPro simulations were compiled to predict the characteristic temperatures of phase crystallizations and transformations under equilibrium conditions. Differential thermal analysis (DTA) was used to cool down samples from 1500 °C to room temperature with various cooling rates (5, 10, 20, 40, and 50 K/min), whereby differences in the number and position of the resulting peaks occurred. To correlate the peaks with specific phase reactions, the microstructure of the variously cooled samples was analysed by means of optical (OM) and scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), wavelength-dispersive X-ray spectroscopy (WDS), electron backscatter diffraction (EBSD) and microhardness tests. The systematic analyses show that the microstructure evolution of the FeCrVBC alloy strongly depends on the cooling rate. For low cooling rates up to 10 K/min, the austenite-ferrite transformation and a marked formation of M7C3 and M23(C,B)6 secondary carbides were observed. At rates of 20 K/min and above, the austenite-martensite transformation takes place, accompanied with a strong increase of the hardness in dendritic areas. By cooling with rates of 40 K/min and higher, the precipitation of M7C3 or M23(C,B)6 secondary carbides cannot be observed anymore, whereas primary M3(C,B) besides MC carbides were detected. Furthermore it was determined, that the very small content of boron (0.05 wt%) strongly influences the (trans-)formation of special carbides, shown by the comparison to its base alloy without boron, the formerly investigated Fe92.7Cr4.2V2.1C1 wt% (FeCrVC). Consequently, strongly depending on the formed carbides the materials hardness and wear resistance can be significantly affected by boron addition. Concluding, the obtained knowledge about the thermal behaviour of the FeCrVBC alloy and the strong impact of a small addition of boron offers the possibility for tailored adjustment of phases and respective properties for a load-adapted tool design.

Effect of boron and carbon addition on microstructure and mechanical properties of the aged gamma-prime strengthened alumina-forming austenitic alloys

The goal of this work was to understand the effects of aging at 800 °C on the microstructures and mechanical properties of two recently-developed AFA stainless steels based on Fe-14Cr-32Ni-3Nb-3Al-2Ti (wt.%), one of which contained small additions of boron and carbon. To that end both the size distributions and growth kinetics of the B2, Laves phase, L12 precipitates present were quantified. While the lattice parameter, morphology, size and coarsening behavior of the L12 precipitates was the same in both AFA alloys, the B and C enhanced the grain boundary coverage by both Laves phase and B2-NiAl precipitates, but suppressed their coarsening. These interstitial additions also suppressed the formation of twins and discontinuous precipitation, which were observed in the B and C-free material. It is shown that the yield strength at 700 °C is largely controlled by the size of the L12 precipitates, with the largest strengthening effect obtained after aging for 2.4 h for both AFA alloys. Longer aging time led to a loss of strength mainly due to the coarsening of the L12 precipitates.

The effect of boron on microstructure and mechanical properties of high-strength cast FeCrVC

This work describes the effect of small boron additions (0.01, 0.05 and 0.1wt%) on the microstructure and mechanical properties of a high strength Fe92.7Cr4.2V2.1C1 (wt%) alloy prepared by applying relatively high cooling rates and pure preparation conditions. The special manufacturing process promotes the formation of martensite, retained austenite and MC (M=V, Cr) carbides and leads to excellent properties under compressive and abrasive loading already in the as-cast state, so that a time-consuming and expensive heat-treatment is not required. Due to microalloying with boron, these properties can be further improved by microstructural changes. Thereby, an increase of the martensite and a drop of the austenite volume fraction was detected by X-ray diffraction (XRD). Furthermore, boron additions lead to the formation of (Fe,M)3(B,C) carbides, which were verified by a combination of electron backscatter diffraction (EBSD) and dispersive X-ray spectroscopy (EDS/WDS) as well as transmission electron microscopy (TEM). With increasing amount of boron, these carbides form an interlocking network-like structure with the MC carbides, which leads in combination with the rising martensite fraction to FeCrMoVBC alloys showing significantly improved abrasive wear resistance and increased hardness compared to the Fe92.7Cr4.2V2.1C1 base alloy. Altogether, microalloying of the FeCrVC alloy with boron combined with a tailored casting process presents a fast and cost-effective method to enhance the performance of the alloy for the application as cutting and forming tool material.

Modification of the α-Ti laths to near equiaxed α-Ti grains in as-sintered titanium and titanium alloys by a small addition of boron

Abstract A small addition of boron (B) changes the morphology of the α-Ti laths in as-sintered Ti–6Al–4V and Ti–10 V–2Fe–3Al to near equiaxed α-Ti grains and increases the number density of the resulting α-Ti grains by up to six folds. TiB forms at about 700 °C during heating to the isothermal sintering temperature and more than 90% of the TiB particles were found inside the α-Ti grains. Transmission electron microscopy (TEM) was used to identify the orientation relationships (ORs) between the TiB and α-Ti phases. Their exact ORs are affected by both the chemistry of the alloy and the processing conditions. The modification of the α-Ti laths and the substantial increase in the number density of the α-Ti grains are attributed to the enhanced heterogeneous nucleation of α-Ti on TiB due to the identified specific ORs and excellent lattice matches between these two phases. In addition, there exists a unique peritectoid reaction between β-Ti and TiB during the subsequent cooling after isothermal sintering by which β-Ti + TiB → α-Ti, which may have contributed to the enhanced heterogeneous nucleation of α-Ti on TiB.

The effect of a small addition of boron on the sintering densification, microstructure and mechanical properties of powder metallurgy Ti–7Ni alloy

The effect of a small addition of boron (B) on the sintering, sintered microstructure and mechanical properties of a Ti-7Ni alloy (wt.%) compacted from −100 mesh hydride-dehydride (HDH) Ti powder has been investigated systematically. An addition of ⩾0.62%B to the Ti–7Ni alloy resulted in fast, near full-densification (⩾99% relative density) within 15min at 1200°C, compared to 95.6% relative density obtained after 120min at 1200°C without B, compacted at 400MPa in both cases. In addition, the pre-eutectoid α phase changed from long parallel α-laths (up to∼500μm) to near-equiaxed α-Ti throughout the microstructure with an addition of ⩾0.31%B. Elemental B was found to be more effective than TiB2 as a sintering aid for Ti-7Ni. A small addition of B increased both the tensile strength and yield strength of Ti–7Ni but at the expense of tensile ductility. The mechanisms behind each of these observations were discussed.

The Influence of a Small Boron Addition on the Microstructure and Mechanical Properties of Ti‐6Al‐4V Fabricated by Metal Injection Moulding

AbstractThe effect of boron additions on the sintering behavior, microstructural development, and mechanical properties of a Ti‐6Al‐4V alloy fabricated by metal injection moulding (MIM) was studied. The addition of boron promotes a significant refinement of the microstructure by changing the microstructure from the typical lamellar to a more equiaxed morphology. The presence of both features: α colonies and α grains were confirmed by electron backscatter diffraction (EBSD) experiments. Furthermore, the pinning effect of TiB particles on grain boundary motion enhances the densification process due to the fact that the separation of pores and grain boundaries is suppressed. As a result of the refinement of the microstructure achieved by adding 0.5 wt% boron to the Ti‐6Al‐4V alloy, excellent tensile (σ0.2 = 787 MPa, UTS = 902 MPa and ε = 12%) and fatigue (endurance limit = 640 MPa) properties were obtained.

Microstructure engineering of titanium alloys via small boron additions

Several studies, dating back to 1950s, were conducted on the addition of boron to titanium alloys, with an aim to improve the stiffness and strength. The majority of these efforts did not lead to successful transition due to shortfalls in mechanical property combinations and insufficient understanding of the effect of boron addition on processing-microstructure-property relationships. Recently, a team of researchers critically evaluated boron-modified titanium alloys to assess their applicability for aerospace applications. Several unique opportunities offered by boron-modified Ti alloys were discovered during these evaluations. Boron is essentially insoluble in titanium and precipitates as fine TiB whiskers. Small additions (~0.1 wt%) of boron to titanium alloys were found to result in dramatically finer grain sizes in the as-cast condition. The presence of TiB precipitates restricts the grain growth at elevated-temperatures, even above the beta transus. Together, these features offer the potential to develop affordable thermo-mechanical processing paths for titanium alloys. This recent work also demonstrated that, via small boron additions, the strength and stiffness of conventional titanium alloys could be increased up to 20% while retaining acceptable fracture and fatigue properties. In this paper, we review this new class of titanium alloys and describe unique benefits obtained via microstructure engineering that were discovered in several recent studies by the authors and their collaborators.

Microstructure engineering of materials

Microstructure of most technical alloys for an engineering application would involve multiple phases that could differ in their physical properties, configuration, morphology, size, volume fraction etc. While the choice of a material for a specific application could involve relevant functional property, often a secondary property (such as freezing range, toughness, corrosion or creep resistance, biological compatibility etc.) could play an overwhelming role in the successful usage of that material. Designing the microstructure, taking the material and processing constraints into account, is one of the major areas of materials research today. In the recent past, several novel processing techniques have emerged that have aimed at obtaining a specific microstructure of the material with an intended application. Severe plastic deformation, electromagnetic processing of melts, multi-step thermo-mechanical processing, rapid solidification are some examples of emerging techniques where research is focused on both the materials as well as the processing technique to obtain the designed microstructure. Kinetic constraints such as rate of deformation and rate of cooling imposed during the processing have an important role in the evolution of microstructure. Several new characterization techniques and tools such as orientation imaging, focused ion beam milling and analytical electron microscopy have aided in assessing the efficacy of the engineering approach taken in the design of a microstructure. Advances in the computational modeling of the processing techniques and simulation of microstructure have opened new avenues in the microstructure engineering. In this thematic volume, we present a collection of five papers that bring out the microstructure engineering in the current state of the art. Arvind Kumar, Miha Zaloznik and Herve Combeau have presented their work on prediction of equiaxed grain structure and macrosegregation in an industrial steel ingot and have compared their results with experiments. Sumantra Mandal, V. Subramanya Sarma and A. K. Bhadhuri have performed grain boundary engineering in alloy D9 through thermo-mechanical processing and have studied influence of process variables and delved on the aspects of micro-mechanisms in depth. Georg J. Schmitz, Bernd Bottger, Jain Eiken, Markus Apel, Antoine Carre, Alexandre Viardin and Gottfried Laschet have reviewed the current status of the phase-field based simulations of microstructure evolution in technical grade alloys. Bikramjit Basu and Garima Tripathi have presented their work on processing and biological evaluation of porous hydroxyapatite/poly methyl methacrylate hybrid composites. Seshacharyulu Tamirisakandala and Dan Miracle have reviewed the efforts to engineer the microstructure of titanium alloys using small additions of boron as alloying element. The materials covered in these studies are of current interest for the industry and the processes chosen are of high impact. This thematic issue has a fine balance of experimental and computational studies on the topic. Articles in this theme were contributed by researchers whose groups have contributed significantly to this area for last several years. We hope that readers will find this issue valuable and informative on the theme of microstructure engineering of materials. The ubiquitous presence of microstructure characterization tools in academic departments of varied engineering disciplines indicates that slowly and steadily, the mesoscale information of materials is being studied and engineered for desired performance. B. S. Murty G. Phanikumar (&) Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai 600036, India e-mail: gphani@iitm.ac.in

Effect of Minor Additions of Boron on Microstructure and Mechanical Properties of As-Cast Near α Titanium Alloy

This work investigates the effect of boron addition on the microstructure and mechanical properties of a near alpha Ti alloy, Timetal 685 in as-cast plus heat-treated condition. While significant refinement of the prior β grain size is seen with small additions of boron, the thickness of α lath (in transformed β structure) increases with increasing boron. At room temperature (RT), tensile yield strength increases marginally, but the ductility drops significantly possibly because of the cracking of TiB phase. At elevated temperature, significant strengthening is observed in the boron containing alloys especially at higher plastic strains. Additionally, the creep resistance shows significant enhancement with boron addition.

Effect of Small Iron, Chromium and Boron Additions as Alloying Elements on Microstructure and Mechanical Properties of Ni<sub>3</sub>Al

This paper investigates the effect of Fe, Cr and B additions, in small proportions, as alloying elements in Ni3Al with the purpose to reduce its intrinsic fragility and extrinsic embrittlement and to enhance, in the same time, its mechanical properties. It represents a development of some previous research works of the authors, proving that Ni3Al-Fe-Cr-B alloys obtained by reactive synthesis (SHS) starting from Mechanically Alloyed powder mixtures have superior both room temperature tensile strength and ductility, and compression ones at temperatures up to 800 °C, than pure Ni3Al. These create premises for their using as superalloys substitutes.

Si0.8Ge0.2계 합금에서 열전특성에 미치는 B의 영향

P-type thermoelectric material was sintered by Hot Press process (HP) and the effect of boron ( at%) addition on the thermoelectric properties were reported. To enhance the thermoelectric performances, the , alloys were fabricated by mechanical alloying (MA) and HP. The carrier of p-type SiGe alloy was controlled by B-doping. The effect of sintering condition and thermoelectric properties were investigated. B-doped SiGe alloys exhibited positive seebeck coefficient. The electrical conductivity and thermal conductivity were increased at the small amount of boron content ( at%). However, they were decreased over 0.5 at% boron content. As a result, the small addition of boron improved the Z value. The Z value of 0.5 at% B doped B alloy was , the highest value among the prepared alloys.

Development of Low Carbon Boron Steel for Wire Drawing

From the mechanical point of view, the successful cold drawing of wire-rods of low carbon steel requires a high ductility and a ratio between the yield stress and tensile strength as lowest as possible, both for diminish the fractures during the process. Small boron additions in the cast of this kind of steel produce an increase in the size of austenitic grain, and consequently the ferritic one, and a diminution of the deformation hardening due to the reduction in the nitrogen content in the solid solution. In this way, the goal of this work is to study the effect of small boron additions (67 to 117 ppm) in the mechanical properties of 5.5 mm diameter wire-rods of low carbon steel. The wire-rods were characterized by means of traction tests, metallographic analysis with optic and electronic microscopy, and the results were compared with the corresponding one for wire-rod of standard steel, i.e., without boron contents. The metallographic analysis confirms the increase in size of ferritic grain. The measured ductility present only slight increases in boron steel, no significant from the quality point of view, however, the ratio between yield stress and tensile strength in boron steels shown a clear improvement respect to the standard. Traction tests in samples obtained at the exit of each one of the matrixes used during the cold drawing process shows an improve in the behavior of low carbon steel with boron contents.

Effects of deformation and boron on microstructure and continuous cooling transformation in low carbon HSLA steels

The continuous-cooling-transformation (CCT) diagram and continuous cooled microstructure were investigated for low carbon (0.05 wt.% C) high strength low alloy steels with/without boron. Microstructures observed in continuous cooled specimens were composed of pearlite, quasi-polygonal ferrite, granular bainite, acicular ferrite, bainitic ferrite, lower bainite, and martensite depending on cooling rate and transformation temperature. A rapid cooling rate depressed the formation of pearlite and quasi-polygonal ferrite, which resulted in higher hardness. However, hot deformation slightly increased transformation start temperature, and promoted the formation of pearlite and quasi-polygonal ferrite. Hot deformation also strongly promoted the acicular ferrite formation which did not form under non-deformation conditions. Small boron addition effectively reduced the formation of pearlite and quasi-polygonal ferrite and broadened the cooling rate region for bainitic ferrite and martensite.

Processing, Microstructure, and Properties of β Titanium Alloys Modified With Boron

The development of next-generation βTi alloys is expected to involve very attractive combinations of strength-toughness-fatigue resistance at large cross sections, improved and affordable thermomechanical processing, and enhanced elevated temperature capability. This article describes the development of βTi alloys that are modified with small boron (B) additions to achieve these goals. Two important aerospace alloys, Ti-15Mo-2.6Nb-3Al-0.2Si and Ti-5Al-5V-5Mo-3Cr microalloyed (0.1%) with B were considered. Ingots that were 70 mm in diameter and 500 mm in length were cast using induction skull melting. A detailed microstructural characterization and tensile property evaluation were conducted. Microalloying with B refines the cast grain size to about 50 µm, which enhances strength and ductility. The effect of B additions on the microstructural stability and properties in the as-cast condition was established. The implications of B additions on the microstructural evolution and affordability of subsequent processing is also discussed.

Bulk amorphous cast iron with small boron addition, produced by powder compaction at high pressure

Amorphous alloys, containing commercial cast iron with the addition of 2 wt.% of boron, were obtained by melt-spinning in the form of ribbons. Bulk amorphous samples were produced by consolidation of powderised amorphous ribbons at high pressure, 7.7 GPa. The samples pressed at room temperature exhibit big, well seen porosity. All the samples compacted at elevated temperatures show a higher relative density compared to the compacts obtained at room temperature. It was found that the compaction process at temperatures up to 520 °C enables production of bulk amorphous alloys. Vicker's microhardness measurements were performed for all the pressed samples. The amorphous ones compacted at higher temperatures show higher microhardness compared to samples compacted at room temperature. It was also observed that partial crystallisation of the amorphous compacts leads to an increase in microhardness even up to 1860 HV0.05.

Direct laser remelting of iron with addition of boron

Previous work has shown that increasing the carbon content of steel powders has a deleterious effect on their direct laser remelting (DLRM) processability. Therefore, other interstitial alloying elements have been investigated to identify if they produce similar effects. This paper reports on the processing of iron powders with small additions of boron by DLRM. It was found that the addition of boron, in the form of iron boride, increased the width of the scanned tracks for a given set of laser parameters and reduced the tendency for the tracks to spheroidise. Boron addition did not have a deleterious effect on processability and to some extent increased component density for a given set of conditions. Other steel samples were processed that contained small additions of iron boride and titanium powder. The inclusion of titanium improved the bonding of the sample to the substrate and reduced the extreme hardness of the material. However, it also significantly reduced the processability of the material.

Effects of environment and temperature on the mechanical behavior of the Ni–19Si–3Nb intermetallic alloy doped with boron and carbon

The effect of small additions of boron and carbon on the environment embrittlement at different temperature of Ni–19Si–3Nb based alloy was investigated by atmosphere-controlled tensile test in various conditions. The results revealed that the Ni–19Si–3Nb base alloy exhibits ductile mechanical behavior (UTS∼1250 MPa, ε∼14%) at room temperature in vacuum (2×10 −4 torr) as well as in pure oxygen atmosphere. This indicates that environmental embrittlement due to water vapor is the major factor to the deterioration of the ductility of Ni–19Si–3Nb base alloy. In parallel, 300 ppm boron addition significantly improves the ultimate tensile strength and the ductility (UTS≥1200 MPa, ε≥12%) in the Ni–19Si–3Nb base alloy at room temperature in various atmosphere of pure oxygen, air (contains 14000 ppm water vapor), and pure water vapor (contains 850 ppm water vapor). In addition, the yield strength of the Ni–19Si–3Nb–0.15B–0.1C alloy increases with temperature, and the maximum yield strength occurs at 873 K. However, the ductility of the Ni–19Si–3Nb–0.15B–0.1C alloy drops significantly when the temperature increases to 973 K.