Alloy Samples Research Articles

Elastocaloric effect of NiTi shape memory alloys manufactured by laser powder bed fusion

To address the challenges posed by the complex processing of NiTi alloys, the additive manufacturing technology has been employed for the preparation of NiTi alloys samples. Up to now, there is limited research on the elastocaloric effects of NiTi alloys manufactured by LPBF. This study focused on the utilization of laser powder bed fusion (LPBF) to fabricate NiTi samples, with a particular emphasis on the influence of laser power, scanning speed and hatch spacing on the microstructure and properties of NiTi alloys. The results indicated that the process parameters affect the stress hysteresis of superelasticity by influencing the Ni content in the NiTi alloys. The higher Ni content, the lower the stress hysteresis. In addition, the critical stress for plastic deformation of the texture in the <001> direction in NiTi alloys is the smallest. When only the P was changed, the proportion of the texture in the <001> direction in the sample increased with the increase of P, the proportion of plastic deformation increased, and the degree of recovery also gradually decreased. Furthermore, at a specific temperature, 10 K higher than the end temperature of austenite transformation, each sample exhibited good superelasticity. In particular, the 1st cooling capacity of the sample with the best elastocaloric effect reached 11.0 K, which was superior to other results obtained by LPBF under similar compressive strain levels.

Study on the effects of bilateral laser-assisted cutting on surface integrity and fatigue life of FeCoCrNiAl0.6 alloy

This study investigates the impact of various cutting parameters in both unilateral and bilateral laser-assisted cutting processes on the surface integrity and fatigue life of FeCoCrNiAl0.6 high-entropy alloy. By utilizing ABAQUS/FE-SAFE simulations and conducting laser-assisted cutting and fatigue tensile tests, differences in surface quality and fatigue life cycles of FeCoCrNiAl0.6 alloy samples under different cutting scenarios were evaluated. The results indicate that in high-speed laser-assisted cutting, an increase in laser speed leads to a progressive decline in surface quality for both unilateral and bilateral methods. Nevertheless, at a laser speed of 4000 mm/s, optimal surface quality is achieved in both approaches, with the bilateral method consistently providing superior results across varying speeds. Regarding residual stress, unilateral laser-assisted cutting at 4000 mm/s produces a surface residual compressive stress of 532 MPa, which is twice as high as that observed at 10000 mm/s. The bilateral method shows a symmetric distribution of residual compressive stress, with peak values of 567 MPa and 528 MPa on the front and back surfaces, respectively. In terms of fatigue life, bilateral laser-assisted cutting demonstrates enhanced performance at 4000 mm/s, achieving a fatigue life cycle that is 4.72 times longer than that of the unilateral method. Overall, bilateral laser-assisted cutting improves the fatigue life of the material through symmetric thermal effects and higher residual compressive stress, particularly at lower laser speeds and optimal cutting depths.

The effect of 3D printing orientation on tensile behaviour and fracture mechanisms of Inconel 718

The manuscript aims to study the effect of 3D printing orientation on the tensile behaviour and fracture mechanisms of samples made of Inconel 718. Components of metals using additive manufacturing techniques are crucial in applications where safety, reliability, and trouble-free operation are essential. Therefore, it is vital to study and understand the behaviour of 3D-printed components under various loading types and predict potential failures. The EOS Nickel Alloy IN718 material sheet provides tensile properties of heat-treated samples (per AMS 5664 procedure) built exclusively in the Z direction. Consequently, the authors extended the investigation to include the tensile behaviour of 3D-printed samples in seven basic orientations within the 3D printing machine’s workspace. For this purpose, the mechanical properties of Inconel 718 alloy samples manufactured using Direct Metal Laser Sintering (DMLS) technology were subjected to uniaxial tensile stress. The samples underwent heat treatment according to the AMS 5664 procedure, with solution annealing and aging temperatures determined using a pseudo-binary phase diagram calculated with Thermo-Calc® software. Post-tensile tests and fracture surface observations were conducted to identify the main failure modes. Microstructural and morphological analyses of 3D-printed INCONEL 718 samples were carried out using light optical microscopy (LOM), scanning electron microscopy (SEM), and electron backscatter diffraction (EBSD) textural analysis. Phase diagrams indicate expected phases such as γ-phase (FCC_A1), δ-phase (NbNi3_D0A), γ’’-phase (Ni3Ti_D024), Laves phase (C14_Laves), and γ’-phase (FCC_L12). Solution annealing was performed above 940 °C while aging treatment was done at temperatures below 800 °C to allow precipitation of γ’ and γ’’ phases. The δ phase also forms during aging. Fractographic examination of the tensile fractures indicated a predominantly quasi-ductile failure mechanism, with fine-sized dimples observed. In the XZ-oriented samples, the measured yield strength was 11 % higher compared to the Z-oriented samples and the yield strength was more than 12 % higher. The difference in mechanical properties between the Z orientation (Rp0.2 = 1284 MPa and Rm = 1429 MPa) and the XZ orientation (Rp0.2 = 1436 MPa and Rm = 1613 MPa) can be mainly attributed to the < 101 > texture in the XZ sample and its more equiaxed grain structure compared to the Z sample.

Investigation into the mechanism of ignition of magnesium alloy plates by high-temperature molten droplet

The ignition and spread of magnesium alloy fires are mainly attributed to the ignition of high-temperature molten metal droplets, but the underlying ignition mechanism remains unclear. This study addresses this knowledge gap by employing metallic aluminum and copper particles heated to temperatures over 1200 °C. Systematically, these heated particles were released at a fixed rate onto a magnesium alloy plate located inside a controlled heating furnace that maintained a constant temperature of 500 °C. Experimental results show that whether there are irregular pores and cracks in the resulting molten product can be used as a criterion for judging whether the magnesium alloy sample ignites. Furthermore, it is worth noting that molten copper droplets of the same size exhibit a higher heat-carrying capacity than their aluminum counterparts when both are heated to the same temperature. In addition, this study expanded the research scope through numerical simulation and analysis, using the PATO (Porous-Material Analysis Toolbox) solver to clarify the transient heat conduction process between the high-temperature droplet and the magnesium alloy plate. Simulations show that heat transfer upon droplet impact is primarily longitudinal, directed toward the base of the material. This results in a significantly higher temperature in the center of the affected magnesium alloy plate than at its periphery. In summary, this study helps to improve the understanding of the dangers of high-temperature molten droplets, and it is of great significance to investigate fire accidents caused by high-temperature molten droplets.

Investigation of microstructure and thermal behavior of CuAlTaGd alloy samples quenched in liquid nitrogen environment after increasing thermal aging times

Investigation of microstructure and thermal behavior of CuAlTaGd alloy samples quenched in liquid nitrogen environment after increasing thermal aging times

Effect of surface orientation on the corrosion behavior of Ni-based single-crystal alloy in a simulated marine atmosphere at 750 °C

DD5 single-crystal alloy samples with different surface orientations were obtained by machining the alloy ingot perpendicular (PP) and parallel (P), respectively, to its solidification direction (SD). The corrosion behaviors of the PPSD and PSD alloy samples were investigated in the atmosphere of moist air + NaCl aerosol at 750 °C. Results showed that during initial corrosion, γ′ phase developed a thin NiO layer with Al internal corrosion product. However, a NiO nodule with an internal Cr2O3 layer was formed on γ phase. As corrosion progressed, the corrosion product gradually grew to a NiO/(Al, Cr)2O3 bilayer, accompanied by internal corrosion consisting of Al2O3. It was also found that the PSD sample with a lower fraction and smaller size of γ’ phases exhibited better corrosion resistance than the PPSD sample. The effect of alloy surface orientation on the corrosion mechanism was discussed.

Microstructure and tribological performance of novel Ni-based alloy cladding with excellent high temperature wear resistance and self-lubrication performance

This paper aims to study the laser cladding of Ni-based alloy coatings with excellent high temperature wear resistance and self-lubrication performance on the surface of parts such that meet complex metallurgical service conditions. The composite alloy powders were formed by adding 3 wt%–11 wt% WS2 and Ti powder to NiCrCoMoBSi alloy powder, and the novel Ni-based alloy samples with high temperature wear resistance and self-lubrication performance were cladded on the surface of Cr28Ni48W5 substrate by laser cladding. The results show that the addition of WS2 and Ti powder had a significant influence on the microstructure evolution and high temperature wear resistance and self-lubrication performance of the samples. The laser cladding coating with 7 wt% WS2 and Ti had the 3 % TiS self-lubricating phase and 19 % enhanced phase with the best microstructure matching relationship, which improved the high temperature wear resistance and self-lubrication performance of the sample. At 800 °C, compared with the Cr28Ni48W5 superalloy substrate, the friction coefficient of the laser cladding coating was 0.22 and the wear ratio was 1.70 × 10−5 mm3 N−1 m−1, which were reduced by 60 % and 54.67 % respectively. The mechanism of the enhanced wear resistance and self-lubrication performance was elaborated.

Reducing the oxidation rate of Cr-coated Zr alloys under high temperature steam environment: An approach of an outer Zr coating

Cr-coated Zr alloys are widely regarded as promising accident-tolerant fuel (ATF) cladding materials. However, the rapid consumption of the Cr coating through both oxidation and diffusion demands a thick coating, which is detrimental to neutron economic. In this study, a thin Zr coating was fabricated on the top of the Cr coating to act as a protective layer, aiming to reduce the oxidation consumption rate of Cr coatings. In-situ weight gain measurements were performed to determine the oxidation kinetics. The microstructural evolution of the coating/substrate interface and the oxide/coating interface were analyzed. The results show that the weight gain rate of the Zr-Cr coated Zr alloy sample is lower than that of the bare Cr-coated Zr alloy samples. An equiaxed grain structure composed of Cr/Zr mixed oxides was observed in the coating, which helps to inhibit elements diffusion and reduce the oxidation rate of Cr coatings. After steam oxidation at 1000 °C for 4 h, the sample structure consisted of the Zr substrate, a Cr2Zr layer, a residual Cr coating, a Cr2O3 layer, a Cr/Zr mixed oxides layer, and a ZrO2 layer.

Microstructure and Mechanical Properties of As-Built Ti-6Al-4V and Ti-6Al-7Nb Alloys Produced by Selective Laser Melting Technology.

Additive manufacturing from metal powders using selective laser melting technology is gaining increasing interest in various industries. The purpose of this study was to determine the effect of changes in process parameter values on the relative density, microstructure and mechanical properties of Ti-6Al-4V and Ti-6Al-7Nb alloy samples. The experiment was conducted in response to a noticeable gap in the research on the manufacturability of the Ti-6Al-7Nb alloy in SLM technology. This topic is significant given the growing interest in this alloy for biomedical applications. The results of this study indicate that by properly selecting the volumetric energy density (VED), the relative density of the material produced and the surface roughness of the components can be effectively influenced. Microstructural analyses revealed similar patterns in both alloys manufactured under similar conditions, characterized by columnar β phase grains with needle-like α' phases. Increasing the VED increased the tensile strength of the fabricated Ti-6Al-4V alloy components, while the opposite effect was observed for components fabricated from Ti-6Al-7Nb alloy. At the same time, Ti-6Al-7Nb alloy parts featured higher elongation values, which is desirable from the perspective of biomedical applications.

Experimental Investigation of the Impact of Loading Conditions on the Change in Thin NiTi Wire Resistance during Cyclic Stretching.

This paper presents the results of an experimental study designed to evaluate the effect of repeated stretching cycles on the electrical resistance change in a NiTi alloy wire. In particular, tests were carried out to determine the effect of the type of loading on resistance change in the investigated wires. Wires with a diameter of 100 μm were used in the research. The experiment was carried out on a dedicated test stand designed for this purpose. During the test, the samples were subjected to 40 identical tensile cycles. The electrical resistance, sample elongation, and tensile force during successive stretching cycles were measured. The conducted research demonstrated the impact of elongation and reorientation of the structure on the resistance change in NiTi alloy thin wires. The research included a comparison of the effect of two different types of loading on the electrical resistance change in the sample. During cyclic stretching of a NiTi alloy sample with constant displacement, a decrease in electrical resistance was observed after each successive stretching cycle. Alternatively, when stretching with a constant force, the value of electrical resistance increased. In both types of loads, the greatest change in resistance value was observed at the initial cycles.

Investigating the Effects of Transition Metals and Activated Carbon on Hydrogenation Characteristics of Severely Deformed ZK60 Processed by High-Energy Ball Milling.

The synergic effects of activated carbon and transition metals on the hydrogenation characteristics of commercial ZK60 magnesium alloy were investigated. Severe plastic deformation was performed using equal-channel angular pressing with an internal die angle of 120° and preheating at 300 °C. The ZK60 alloy samples were processed for 12 passes using route BA. The deformed ZK60 alloy powder was blended with activated carbon and different concentrations of transition metals (Ag, Pd, Co, Ti, V, Ti) using high-energy ball milling for 20 h at a speed of 1725 rpm. The amount of hydrogen absorbed and its kinetics were calculated using Sievert's apparatus at the higher number of cycles at a 300 °C ab/desorption temperature. The microstructure of the powder was analyzed using an X-ray diffractometer and scanning electron microscope. The results indicated that 5 wt% activated carbon presented the maximum hydrogen absorption capacity of 6.2 wt%. The optimal hydrogen absorption capacities were 7.1 wt%, 6.8 wt%, 6.7 wt%, 6.64 wt%, 6.65 wt%, and 7.06 wt% for 0.5 Ag, 0.3 Co, 0.1 Al, 0.5 Pd, 2 Ti, and 0.5 V, respectively. The hydrogen absorption capacities were reduced by 35.21%, 26.47%, 41.79%, 21.68%, 26.31%, and 26.34% after 100 cycles for 5C0.5Ag, 5C0.3Co, 5C0.1Al, 5C0.5Pd, 2Ti, and 5C0.5V, respectively. Hydrogen absorption kinetics were significantly improved so that more than 90% of hydrogen was absorbed within five minutes.

Influence of grain sizes and secondary phases on the mechanical behavior and corrosion resistance in a non-equiatomic NiCrCoFeMoAlTi high-entropy alloy

Single-phase face-center cubic (FCC) structured Ni27.7Cr24Co23.5Fe15.7Mo1.6Al3Ti4.5 high-entropy alloy (HEA) samples with different grain sizes were first achieved, suggesting smaller grain size improved corrosion resistance and strength. Subsequently, aging was performed on the sample with the smallest grain size (∼9.5 μm), leading to the formation of lots of nano-sized spherical coherent L12 precipitates at FCC grain interior, along with some σ phase and non-spherical L12 precipitates at grain boundaries. Therefore, a superior combination of mechanical and corrosion properties was achieved. Secondary phases caused chemical and structural changes in the passive film due to galvanized corrosion, leading to slightly lower corrosion resistance.

A spectral bias-error stepwise correction method of plasma image-spectrum fusion based on deep learning for improving the performance of LIBS

Poor spectral stability seriously hinders the wide application of laser-induced breakdown spectroscopy (LIBS), so how to improve its stability is the focus, hotspot, and difficulty of current research. In this study, to achieve high precision quantitative analysis under complex detection conditions, utilizing the fusion of multi-dimensional plasma information and the integration of physical models and algorithmic models, a spectral bias-error stepwise correction method of plasma image-spectrum fusion based on deep learning (SBESC-PISF) was proposed. In this method, based on the statistical properties of LIBS spectra, the actual obtained spectra were decomposed into three parts: the ideal spectral intensity related only to the element concentration, and the spectral bias and spectral error caused by the fluctuation of complex high-dimensional plasma parameters. Further, the deep learning methods were used to fully excavate all the effective features in the plasma images and spectra to invert the complex high-dimensional plasma parameters according to the physical models. Finally, the estimation models of spectral bias and spectral error were established based on these features, to realize the high-precision correction of spectral intensity. To verify the feasibility of SBESC-PISF, the spectra of aluminum alloy samples obtained under three complex detection conditions were used for analysis. Under the experimental condition of laser energy fluctuation, after correction by SBESC-PISF, R2 of the three calibration curves was all increased to 0.999, RMSE and STD of the validation set (RMSEV, STDV) were reduced by 55.246 % and 50.167 %, respectively. Under the experimental condition of defocusing amount fluctuation, R2 was also all increased to 0.999, RMSEV and STDV were decreased by 58.201 % and 51.006 %, respectively. When the laser energy and defocusing amount fluctuate simultaneously, R2 was increased to 0.999, 0.996 and 0.988, RMSEV and STDV were reduced by 58.776 % and 54.397 %, respectively. These experimental results demonstrate that the spectral fluctuation correction of SBESC-PISF under complex detection conditions is effective and has wide applicability.

Improvement of magnetic properties and hardness by alloying Mo to a FeCrCo alloy

In most of the technologies used for improving material properties, the enhancement of some properties usually leads to the degradation of others. In this study, we demonstrated that we were able to simultaneously improve hardness, coercivity, and remanence by alloying an FeCrCo alloy with Mo by engineering its α → α1 + α2 spinodal decomposition. We prepared six Mo-alloyed samples and subjected them to the appropriate aging protocols. As aging progressed, hardness increased from 272 to 447 HV and coercivity increased from 47 to 592 Oe in the alloyed samples. Remanence gradually increased from 52 to 98 Am2/kg, and then decreased to 82 Am2/kg in the final stage of the aging process. By adding Mo to six individual FeCrCo samples aged to different stages, we increased the hardness of these samples by 3 %, 8 %, 7 %, 8 %, 5 %, and 10 %, respectively. At the same time, we increased their coercivity by 74 %, 13 %, 19 %, 4 %, 14 %, and 9 % respectively and their remanence by 82 %, 63 %, 4 %, 4 %, 9 %, and 13 %, respectively. We used data drawn from scanning transmission electron microscopy, first-principles calculations, and magnetic force microscopy in order to elucidate the reasons behind the observed enhancements of magnetic properties in the FeCrCoMo alloy.

Experimental investigation of stick-slip behaviors in dry sliding friction

Friction-induced vibration, particularly the bothersome stick-slip behavior, is a significant contributor to machine damage and component failure. In this study, the vibrational displacement, sound pressure, and coefficient of friction (COF) of several metal or alloy samples in dry conditions are tested using a reciprocating friction force test apparatus. It is found that the stick-slip behavior is more likely to occur at low sliding speeds and high normal loads. Furthermore, under the same working conditions, increasing the surface roughness of the sample or enhancing the hardness difference between the sample and the counterpart can mitigate the stick-slip behavior during the friction process. By analyzing the characteristic parameters of the stick-slip behavior, it is found that the temporal period and the stick-time decrease significantly with an increase in relative sliding speed. Additionally, the amplitude and intensity of the friction-induced noise increases with the increase of the relative sliding speed and normal load. The frequencies of the sound pressure are primarily concentrated around the natural frequency of the frictional system. Finally, we extract the COF and find that the average COF as well as the maximum and minimum COF first decreases sharply, and then becomes stable with the increase of the relative sliding speed due to the transition of friction state from stick-slip behavior to smooth sliding.

Experimental and theoretical results of gamma shielding features for copper based shape memory alloys

In this study, the gamma ray attenuation characteristics for CuAlNi shape memory alloys with different proportions of Sn doping was investigated. We determined the mass attenuation coefficient (μ/ρ) of CuAlNiSn alloys both experimentally and theoretically within an energy range of 59.5–1332.5 keV. The experimental measurements were made using a high purity Germanium detector (HPGe) and theoretical calculations were made using WinXCOM program. To evaluate the gamma radiation shielding abilities of the alloy samples, the obtained (μ/ρ) values were used to determine the gamma protection parameters μ, HVL, TVL, MFP, and Zeff. In addition, the radiation protection efficiency (RPE) parameter was determined using gamma ray intensities in the absence and presence of the attenuator. Further analysis of the samples was conducted using a Rigaku Miniflex 600 model computer-controlled X-ray diffractometer (CuKα & λ = 1.5405 A0). The crystallographic structure of the alloys before and after irradiation was investigated. Other analysis which include EDX analysis (to investigate the chemical content) and SEM analysis (to investigate the microstructure) were conducted. According to result outcomes, gamma ray radiation did not affect the shape memory properties of structure. Another interesting observation is that, the radiation attenuation properties increase with increasing Sn concentration. Finally, we discovered that the CuAlNiSn4 alloy (which has the highest doping rate) provides good protection especially at low energy levels.

Development of Ti–Zr–Mn–Cr-(V–Fe) based alloys for hydrogen feeding system in hydrogen metallurgy application

AB2-type Ti-based hydrogen storage alloys are considered promising candidates for the hydrogen feeding system in hydrogen-metallurgy application. In this work, Ti0·87Zr0.15MnxCr1.75-xV0.25 (x = 1.25–1.5), Ti0·87Zr0·15Mn1·5Cr0.5-y(VFe)y (y = 0.25–0.43) and Ti0.85+zZr0.15Mn1·5Cr0·07(VFe)0.43 (z = 0–0.05) alloys were synthesized using induction levitation melting, where ferrovanadium VFe consists of 80 wt% V and 20 wt% Fe. Subsequently, their microstructures and hydrogen storage performances were systematically investigated. The results demonstrate that all alloy samples exhibit a single C14 Laves phase structure with uniform element distribution. With the increment of Cr/Mn, VFe/Cr ratio, or Ti stoichiometry, the alloys exhibit enhanced hydrogen storage capacity, accompanied by a decrease in hydrogenation equilibrium pressure because of interstitial volume expansion or hydrogen affinity improvement, which is also supported by density functional theory calculations. Considering the application of hydrogen metallurgy, Ti0·86Zr0·15Mn1·5Cr0·07(VFe)0.43 alloy is regarded as a promising candidate, exhibiting a saturated capacity of 2.01 wt% H2, an effective reversible capacity of 1.91 wt% H2, rapid hydrogenation kinetics, excellent cyclic durability and low costs. This work provides valuable insights into the compositional design of hydrogen storage alloys for the hydrogen feeding system in hydrogen metallurgy applications.

A high throughput in-situ measurement of heat transfer in successive non-isothermal forming of sheet alloys

The measurement and control of the heat transfer of sheet alloys in successive non-isothermal forming cycles is crucial to achieve the desired post-form properties and microstructure, which could not as of yet be realized by using traditional test facilities. In the present research, a novel heat transfer measurement facility was designed to generate and subsequently measure the in-situ heat transfer from a sheet alloy to multi-mediums such as forming tools, air, lubricant and coating. More importantly, the facility was able to use a single sheet alloy sample to perform successive non-isothermal forming cycles, and subsequently obtain high throughput experimental results including the temperature evolution, cooling rate, mechanical properties and microstructures of the alloy. The high throughput in-situ heat transfer measurement facility identified that the cooling rate of AA7075 was 152 °C/s and the mechanical strength was over 530 MPa in the 1st forming cycle. However, it decreased to less than the critical value of 100 °C/s in the successive 10th forming cycle, leading to a low mechanical strength of only 487 MPa. The identified variations that occur in the successive non-isothermal forming cycles would improve the consistency and accuracy of part performance in large-scale manufacturing.

Springback characteristics and influencing laws of four-axis flexible roll bending forming for aluminum alloy.

This study aims to solve the problem of springback control of aluminum alloy components in the rolling process, and the method of combining experiment and simulation is adopted. Firstly, a series of aluminum alloy samples are designed, and the four-axis flexible bending machine is used for precision roll bending. Secondly, the three-dimensional (3D) shape change data of the workpiece before and after roll bending is monitored and recorded in real-time by a high-precision 3D scanner. Meanwhile, aiming at different rolling process parameters of each group (including roll bend speed, feed rate, pre-deformation amount, mold curvature radius, and other factors), advanced finite element software is used to carry out detailed simulation and calculations. In addition, the coincidence is compared and analyzed between the actual experiment results and the simulation prediction. The stress-strain distribution and springback evolution of aluminum alloy during roll bending are described accurately. The experimental and simulation results show that the springback rate of aluminum alloy fluctuates in the range of 5% to 15% after four-axis flexible roll bending, and the specific springback value is influenced by various process parameters. For example, under the premise of keeping other conditions unchanged, when the roll bending speed is increased from 30mm/s to 60mm/s, the springback rate shows an upward trend of about 3%. By increasing the feed rate by 20%, an average decrease of about 7% in springback quantity is observed. It can be seen that the increase in roll bending speed can aggravate the springback phenomenon, and the appropriate increase in feed rate can play a certain role in restraining the springback. Further analysis shows that the choice of the mold curvature radius and pre-deformation amount also has a decisive influence on the springback characteristics. There is a nonlinear relationship between the two parameters and the amount of springback. Changing these two parameters in a specific range can effectively regulate the springback effect.

Analysis of methods for calculating the module of elasticity during dynamic instrumental indentation

The results of a comparative analysis of three methods for calculating the elastic modulus during dynamic instrumental indentation are presented: in accordance with GOST R 56474, GOST R 8.748 and the proposed original method based on data from optical analysis of the indentation using prepared samples of alloys 20Х25Н20С2, 20Х23Н18 and BrANZhNMts9-4-4- 1.