Phase Quantification Research Articles

Phase formation maps in Zr48Cu46.5Al4Nb1.5 bulk metallic glass composites as a function of cooling rate and oxygen concentration

A design of experiments (DoE) approach was employed to systematically characterize the effects of both oxygen concentration and cooling rate on the amorphous and crystalline phase fractions in the Zr48Cu46.5Al4Nb1.5 bulk metallic glass composite (BMGC) alloy. Specifically, four distinct oxygen concentrations and five distinct cooling rates were used. Phase quantification was achieved using Rietveld refinement of synchrotron X-ray diffraction (XRD) data. Electron probe microanalysis (EPMA) using wavelength dispersive spectroscopy (WDS) revealed that the big-cube crystalline phase may scavenge oxygen from the amorphous matrix of a 2864 ± 47 wppm oxygen sample. Transmission electron microscopy (TEM) of the alloy containing 340 ± 25 wppm oxygen revealed the presence of an amorphous matrix with partially-transformed colonies of B2 (Pm-3m) where the transformation product was a B19’ superstructure (Cm space group) instead of the more common B19’ superstructure (P21/m space group); this was in agreement with the Rietveld refinement results. An orientation relationship between the B2 and B19’ phases was observed as expected. Finally, it was possible to produce thicker sections (5 mm vs. 3.5 mm) with the desired composite structure (∼80% amorphous fraction with ∼20% B2/B19’) compared with previous BMGC studies on similar compositions.

Chan-Vese segmentation of SEM ferrite-pearlite microstructure and prediction of grain boundary

The image processing of microstructure for design, measure and control of metal processing has been emerging as a new area of research for advancement towards the development of Industry 4.0 framework. However, exact steel phase segmentation is the key challenge for phase identification and quantification in microstructure employing proper image processing tool. In this article, we report effectiveness of a region based segmentation tool, Chan-Vese in phase segmentation task from a ferrite- pearlite steel microstructure captured in scanning electron microscopy image (SEM) image. The algorithm has been applied on microstructure images and the results are discussed in light of the effectiveness of Chan-Vese algorithms on microstructure image processing and phase segmentation application. Experiments on the ferrite perlite microstructure data set covering a wide range of resolution revealed that the Chan-Vese algorithm is efficient in segmentation of phase region and predicting the grain boundary.

Correlative Microscopy – Color Etching vs. Electron Backscatter Diffraction: Application Potenials and Limitations

Abstract The development of new materials and heat treatment concepts requires extensive structural analyses. An example for this is the development of extremely durable and deformable steels using the “Quenching and Partitioning” (Q&P) heat treatment. The aim is to achieve a balanced ratio of dispersed austenite islands in a martensitic matrix to achieve maximum strength at a moderate deformability. There is a wide range of different procedures for the microstructure characterization and phase quantification. Color etchings present an efficient alternative to time-consuming electron-microscopic examinations via EBSD. In the present work, comparative examinations regarding the reliability of light-optical analyses via color etching were carried out. It was shown that process-related factors might lead to significant misinterpreations. Especially the production conditions of the raw material are an essential influencing factor regarding the etching behaviour und thus the interpretation of the micrographs.

Ultrashort-pulse laser as a surface treatment for bonding between zirconia and resin cement

ObjectivesTo evaluate ultrashort-pulse laser (UPL) as a surface treatment for improved bond strength to Yttria-tetragonal zirconia polycrystalline (Y-TZP). MethodsFully-sintered Y-TZP samples received either no treatment (CTL), or were treated by alumina blasting (ALB), tribochemical silica coating (SIL), or one of two UPL patterns: multiple pulses laser surface dots with 2.5μm spacing (8mJ, 10kHz)(LSD); or single pulse laser surface lines with 2.5μm spacing (4mJ, 6.7kHz)(LSL). Surface roughness, wettability (contact angle), and quantification of crystalline phases were evaluated for each group (n=3/group). Y-TZP treated slabs were cemented to resin composite slabs using silane and 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-containing adhesive. Beams from the Y-TZP/resin blocks were microtensile tested (n=5/group) after 48h water incubation (37°C) with or without subsequent thermocycling (5–55°C, 5000 cycles). ResultsAll surface treatments increased surface roughness values versus control (P<0.001). Contact angles were lowest for SIL (6.57±2.37°) and highest for control (50.97±6.30°). LSL and LSD were the only treatments that did not increase the relative monoclinic phase. All surface treatments significantly increased microtensile bond strengths (μTBS) compared with the control group (P<0.001), with highest values for UPL (LSD: 35.40±4.53MPa>LSL: 31.84±8.46MPa>SIL: 19.95±3.99MPa=ALB: 19.51±2.55MPa>CTL: 14.51±2.23MPa). Thermocycling significantly reduced bond strength for all treatments in a surface treatment-dependent manner. SignificanceThe ability of UPL to alter Y-TZP surface morphology, increase wettability and μTBS without increasing the monoclinic content suggests its potential to improve bonding to the underlying resin cement and tooth without compromising the strength of the restoration.

Grain Boundary Detection and Phase Segmentation of SEM Ferrite–Pearlite Microstructure Using SLIC and Skeletonization

In this paper, we report an efficient segmentation and grain boundary detection process using modern image processing operators like simple linear iterative clustering and skeletonization. Accurate phase segmentation is the major requirement for any phase identification and quantification operations. The proposed image processing methods have been experimented on the in-house generated 48 scanning electron microscopy (SEM) microstructures obtained from plain carbon steel samples containing 0.1, 0.22, 0.35 and 0.48 wt%C and have been subjected to both annealing and normalizing treatments. The microstructures for dataset have been captured in SEM using secondary electron mode over a wide range of magnification × 500–× 5000. The experimental results significantly validate the segmentation of ferrite and pearlite regions. Also, the grain boundary detection results appear to be plausibly effective in case of ferrite–ferrite and ferrite–pearlite boundaries. However, the grain boundary detection efficiency is found to be relatively poor in case of pearlite–pearlite boundary. The overall performance of the proposed image processing technique in context of ferrite–pearlite steel SEM images shows promising results in all circumstances of compositional range, heat treatment and magnification.

Optimization and Characterization of Si3N4 Layer for Wear Resistant Ti-Al-N/Si3N4 Nano- Composite Coatings

Machining Custom 465 steel at high speeds usually at 20-30% lower than ordinary stainless steel leads to excessive tool wear and thereby affecting the tool life. In such case tool life can be increased by coating a nano-composite layer of Ti-Al-N/Si3N4 which exhibits high strength, hardness, toughness, resistance to oxidation and thermal shock. Particularly, Si3N4serves as an interfacial phase in nano-composite layer is thermodynamically stable phase at high temperatures up to 1850˚C along with high oxidation resistance which might reduce the heat flow between tool-workpiece interfaces leading to high thermal stability of cutting tool. Physical vapor deposition techniques can be used to develop Ti-Al-N/Si3N4 nano-composite coating which involves typically 81 trial depositions in order to obtain optimized process parameters for Si3N4. Here we attempt to reduce the number of trails by design and optimization of process parameters which was efficiently achieved at faster rate by applying the Taguchi design. In present work, we used Taguchi orthogonal (L9) array to conduct the 9 experiments and obtained optimum process parameters for Si3N4 coating. Based on the design we deposited Si3N4nanocoating using RF magnetron sputtering process with 4 factor and 3 level process parameters namely, Ar:N2 gas mixture, RF Power, deposition time, and deposition pressure on high speed steel (HSS), tungsten carbide (WC) and Si (100) substrates. Atomic Force Microscopy (AFM) studies were carried for surface roughness, topography, and phase contrast imaging. Glancing incidence X-ray diffraction (GIXRD) studies were performed for the identification and quantification of crystalline and amorphous phase. Field Emission Scanning Electron Microscopy (FE-SEM) studies were performed for the film thickness and grain size of Si3N4layers.

Strength and hardness studies of C44300 tube to AA7075-T651 tube plate threaded and unthreaded dissimilar joints fabricated by friction welding process

Friction welding is an important process used nowadays especially for joining dissimilar metals in engineering and allied industries. The joining of dissimilar materials is different from the conventional materials and needs proper care and technology advancement. The objective of the present research is to investigate the strength of friction welded joints in the absence of backing block. Two conditions of tube and tube plates with thread pair and without thread pairs are considered for the experimentation. The effect of process parameters on the strength has been arrived. Microstructure at the weld joint interface indicates the high level of refinement at the weld zone. Scanning Electron Microscopic (SEM) images are used for investigating the intermolecular bonding of the tube and tube plate. Micro cracks are observed at the interface. Absence of backing block is the cause for the defect. Energy Dispersive Analysis (EDX) and X-Ray Diffraction (XRD) test are used for analyzing the material properties and quantification of crystalline phases.

The immobilization of potentially toxic elements due to incineration and weathering of bottom ash fines.

Incineration bottom ash fines (≤ 125 μm) are known to contain potentially toxic elements (PTEs) and inorganic salts. The most abundant PTEs in the fines were Zn (0.5%), Cu (0.25%), Pb (0.12%), Mn (0.08%) and Cr (0.03%). The systematic quantification of the mineral phases and PTEs associated with them was performed with a multimethod approach using quantitative XRD, phase mapping with PhAse Recognition and Characterization (PARC) software and microprobe analysis. The mineral phases in the fines can be categorized as follows: 1) residual phases (e.g., quartz), 2) incineration phases (e.g., melilitic slag and iron oxides) and 3) quenching/weathering phases (e.g., calcite, ettringite, gypsum, hydrous Fe- and Al-oxides). Among the incineration phases, the melilitic slag was observed to contain Cr, Cu and Zn with 0.02%, 0.13% and 0.19%, respectively. In order of predominance, the weathering phases containing the most PTEs were: calcite < ettringite < hydrous Al-oxides < hydrous Fe-oxides. More than 70% of the phases in the BA fines were formed during incineration and weathering processes that explain the enrichment of PTEs in the smaller particles. During the one-batch leaching test, dissolution of weathering phases, especially ettringite, was observed (total mass loss: 7.2%).

Investigating the Dynamics of MCMV-Specific CD8+ T Cell Responses in Individual Hosts.

Infection by Cytomegalovirus (CMV) is characterized by the massive expansion and continued maintenance of CMV-specific CD8+ T cells for certain CMV-derived peptides. This phenomenon called “memory inflation" has made CMV a primary target for the generation of T cell based vaccine vectors against various diseases. However, many aspects concerning the generation and maintenance of the inflationary CD8+ T cell response still remain to be resolved. In this study, we combined experimental data and mathematical models to analyze the dynamics of circulatory inflationary CD8+ T cells within individual mice infected by MCMV. Obtaining frequent measurements on the number and frequency of CMV-specific CD8+ T cells up to 70 days post infection, we find that mathematical models assuming differing viral stimuli during acute infection and the inflationary phase provide a better description for the observed dynamics than models relying on similar viral stimuli during both phases. In addition, our analysis allowed a detailed quantification of the different phases of memory inflation within individual mice (1st-expansion - contraction - 2nd expansion/maintenance) indicating remarkable consistency of the timing of these phases across mice, but considerable variation in the size of the individual responses between mice. Our analysis provides a first step toward generating a mechanistic framework for analyzing the generation and maintenance of inflationary CD8+ T cells while accounting for individual heterogeneity. Extending these analyses by incorporating measurements from additional compartments and more prolonged sampling will help to obtain a systematic and quantitative understanding of the factors regulating the process of memory inflation.

The influence of mechanical activation process on the microstructure and mechanical properties of bulk Ti2AlN MAX phase obtained by reactive hot pressing

Abstract The effect of mechanical activation process on the microstructure and mechanical properties of bulk nanostructured Ti2AlN compound has been investigated in this work. The mixture of Ti and AlN powders was prepared in a 2:1 molar ratio, and a part of this powder was subjected to a high-energy milling process under argon atmosphere for 10 h using agate as grinding media. Finally, the densification and formation of the ternary Ti2AlN MAX phase through solid state reaction of both unmilled and milled powders were carried out by hot pressing under 15 or 30 MPa at 1200 °C for 2 h. The microstructure of precursor powder mixtures and the consolidated samples was characterized by using X-ray diffraction (XRD) and a scanning electron microscope equipped with an energy dispersive X-ray spectroscopy (SEM/EDS). The X-ray diffraction patterns were fitted using the Rietveld refinement for phase quantification and to determine their most important microstructural parameters. Microstructure and mechanical properties of the consolidated samples were correlated with the load used for the hot pressing process. The substantial increase of hardness, the higher densification and the lower grain sizes observed in the samples prepared from the activated powders were attributed to the formation of second phases like Ti5Si3 and Al2O3.

Comparison of the Mineralogy of Iron Ore Sinters Using a Range of Techniques

Many different approaches have been used in the past to characterise iron ore sinter mineralogy to predict sinter quality and elucidate the impacts of iron ore characteristics and process variables on the mechanisms of sintering. This paper compares the mineralogy of three sinter samples with binary basicities (mass ratio of CaO/SiO2) between 1.7 and 2.0. The measurement techniques used were optical image analysis and point counting (PC), quantitative X-ray diffraction (QXRD) and two different scanning electron microscopy systems, namely, Quantitative Evaluation of Materials by Scanning Electron Microscopy (QEMSCAN) and TESCAN Integrated Mineral Analyser (TIMA). Each technique has its advantages and disadvantages depending on the objectives of the measurement, with the quantification of crystalline phases, textural relationships between minerals and chemical compositions of the phases covered by the combined results. Some key differences were found between QXRD and the microscopy techniques. QXRD results imply that not all of the silico-ferrite of calcium and aluminium (SFCA types) are being identified on the basis of morphology in the microscopy results. The amorphous concentration determined by QXRD was higher than the glass content identified in the microscopy results, whereas the magnetite and total SFCA concentration was lower. The scanning electron microscopy techniques were able to provide chemical analysis of the phases; however, exact correspondence with textural types was not always possible and future work is required in this area, particularly for differentiation of SFCA and SFCA-I phases. The results from the various techniques are compared and the relationships between the measurement results are discussed.

Crack-healing during two-stage crystallization of biomedical lithium (di)silicate glass-ceramics

ObjectiveThe study is aimed to evaluate the two single commercially available two-step lithium-(di)silicate systems by analyzing their parent glass composition and studying the quantitative crystalline and glass phase evolution during the second stage heat-treatment. The mechanical repercussions of the crystallization firing were evaluated using strength and fracture toughness tests. MethodsXRF and ICP-OES were used to determine the oxide composition of the parent glasses in Suprinity PC (Vita Zahnfabrik) and IPS e.max CAD (Ivoclar-Vivadent). The crystalline phase of both materials was determined by quantitative XRD and the G-factor method in the partially and post-crystallization states. The oxide composition of the residual glass phase was derived by subtracting the chemistry of the crystalline phase fractions from the parent glass composition. Mechanical testing of biaxial flexural strength and fracture toughness were used to demonstrate how crack-like defects behave during crystallization. ResultsThe two tested lithium (di)silicate systems showed strong differences in oxide composition of the parent glass. This showed to influence the transformation of lithium metasilicate in lithium disilicate, with the former remaining in high vol.% fraction in the post-crystallization Suprinity PC. In IPS e.max CAD cristobalite precipitated at the surface during the second-heat treatment. Strength and fracture toughness tests revealed that crack in both materials, whether introduced by grinding or indentation, heal during the crystallization firing. Cristobalite seemed to have contributed to a surface strengthening effect in IPS e.max CAD. SignificanceAccurate crystalline phase quantification aids in the determination of the residual glass composition in dental glass-ceramics. For both systems crystallization firing induced healing of cracks generated by CAM grinding.

Particle scale modeling of CuFeAlO4 during reduction with CO in chemical looping applications

Particle scale models that couple reaction phenomena to changes in the solid-state chemistry of an oxygen carrier system are critical to the advancement of the chemical looping concept by allowing for a means to assess process scale up. This work presents an analysis of the reduction for a CuFeAlO4 oxygen carrier with Carbon Monoxide (CO). The analysis was utilized to aid in the application of particle scale model representation of the carrier system. An experimentally driven study was conducted to provide an array of operational/parametric data sets for the analysis and their impact accessed. Quantification of the cubic spinel oxide phase and changes due to lattice oxygen depletion from reduction were explored to link the solid-state chemistry changes to the reaction progression. Reduction occurred in a multistep process as oxygen was depleted from the structure. Oxygen bound to Cu cations were the first to react with CO. As oxygen was depleted further phase re-orientation occurred resulting in an iron based aluminate (FeAl2O4) with discrete metallic copper present. FeAl2O4 was further depleted of oxygen to metallic Fe and alumina. The multistep process was emulated through the use of a multi-interface Grainy pellet model. To add to the utility of the model, the effects of product gas, CO2, on the reaction progression were incorporated into the description. In addition, the catalytic effects of the Boudouard reaction were examined and incorporated into the representation adding to the novelty of the work.

Numerical neutron attenuation correction for partially-illuminated powder samples

Chemical phase quantification from neutron diffraction measurements relies on accurate Bragg peak intensities at all diffraction angles. Amongst others these intensities are influenced by the total distance that the neutron beam has traversed through the sample in reaching the contributing volume segment and the distance from the contributing volume segment to the outer edge of the sample in the direction of the neutron detector. Since the total path length is dependent on the diffraction angle, gauge volume position inside the sample, as well as the sample dimensions and shape, the measured diffraction pattern should be corrected to account for this non-constant attenuation effect. Results show that in highly attenuation materials this can influence refined parameters during chemical phase quantification. A module was designed and integrated into the data reduction system ScanManipulator used at the neutron diffraction facility at the SAFARI-1 research reactor. The correction technique can further be used to accurately determine diffraction patterns obtained from position-resolved neutron diffraction experiments.

A Comparative Study of Experimental Configurations in Synchrotron Pair Distribution Function.

The identification and quantification of amorphous components and nanocrystalline phases with very small crystal sizes, smaller than ~3 nm, within samples containing crystalline phases is very challenging. However, this is important as there are several types of systems that contain these matrices: building materials, glass-ceramics, some alloys, etc. The total scattering synchrotron pair distribution function (PDF) can be used to characterize the local atomic order of the nanocrystalline components and to carry out quantitative analyses in complex mixtures. Although the resolution in momentum transfer space has been widely discussed, the resolution in the interatomic distance space has not been discussed to the best of our knowledge. Here, we report synchrotron PDF data collected at three beamlines in different experimental configurations and X-ray detectors. We not only discuss the effect of the resolution in Q-space, Qmax ins of the recorded data and Qmax of the processed data, but we also discuss the resolution in the interatomic distance (real) space. A thorough study of single-phase crystalline nickel used as standard was carried out. Then, selected cement-related samples including anhydrous tricalcium and dicalcium silicates, and pastes derived from the hydration of tricalcium silicate and ye’elimite with bassanite were analyzed.

Modal abundance, density and chemistry of micrometer-sized assemblages by advanced electron microscopy: Application to chondrites

Numerous geosciences samples display a multi-scale mineralogical heterogeneity for which it is challenging to obtain spatially resolved quantitative chemical data. It is the case for chondritic meteorites, which can contain up to 10 different phases with grain size ranging from the nanometer to the millimeter. We developed a method providing multiple physical and chemical information by advanced scanning electron microscopy (SEM), hyperspectral energy dispersive X-ray spectroscopy (EDX) and electron probe micro-analyses (EPMA). The method includes: i) infra-micrometric low-voltage EDX mapping and innovative post-acquisition hyperspectral data analysis (based on both clustering and multiple linear least square fitting) which allow phase mapping and quantification of the modal abundances; ii) EPMA of chemical end-members to upgrade the phase map into a quantified chemical map; iii) physical modeling of the EDX background, used as a proxy of the density. Density maps can be obtained with a precision of ~10%; iv) determination of the bulk sample composition by combining modal abundances, chemical analysis and density measurements.The approach is applied to three well-known chondrites (Murchison, Paris and Orgueil), showing heterogeneous grain sizes and mineralogy. Areas of ~250 ∗ 250 μm2 were mapped with a pixel size of 250 nm to determine the modal abundances, size distribution, circularity and densities of all phases, as well as the matrix bulk compositions. Taking bulk wet chemistry data as reference, ACADEMY leads to a better match than published defocused beam EPMA measurements. We demonstrate that choosing a Fe-rich, hydrated standard (a biotite) to quantify phyllosilicate by EPMA improves the quantification by up to 10%, and we ultimately retrieve the Mg/Si ratio with a 1% precision. We called this method ACADEMY for Analyzing the Composition, the modal Abundance and the Density using Electron MicroscopY. A code was developed and was made available online so that ACADEMY can be applied to other materials.

A new method for simple quantification of Laves phases and precipitates in TiCr2 alloys

Laves phases are encountered in many AB2 intermetallic compounds. They consist of one cubic (C15) and two hexagonal (C14 and C36) phases. All of them have characteristic cavities, which favour the hosting external molecules, leading to potential application for hydrogen storage. From a crystallographic point of view, Laves phases consist of different stackings of the same units. Hence, many Bragg reflections of Laves phases overlap and the accurate phase quantification is hindered through conventional methods. Here we propose a simple method, based on the relative intensities of three diffraction peaks, to perform a first quantification of Laves phases. No crystallographic background is required. The method is tested using laboratory diffractometer on a set of TiCr samples produced with different compositions and thermal treatments. Synchrotron radiation data were used for comparison and to assess lattice parameters and atomic structure as a function of Cr/Ti. Considering the relative phase fractions computed by Rietveld refinements as a reference, ∼90% of the phase fractions computed by FQA differ by less than 15%. Precipitates were identified and quantified combining X-ray diffraction and electron microscopy.

Critical research study of quantification methods of mineralogical phases in cementitious materials

Cement or clinker phase quantification is considered as an important task for the control of the cement quality and its manufacturing conditions. Indeed, precise clinker phase quantification allows the prediction of cement properties and the identification of possible anomalies during its production process. However, the complexity of cement and clinker mineralogy makes this step very difficult. In this work, a study was carried out to quantify the mineralogical phases of four Portland cements and two clinkers using two different methods: The first is the traditional Bogue method and the second is X-ray diffraction coupled with Rietveld refinement. The comparison method results showed that the Rietveld method is the most precise and powerful tool for cement and clinker phase quantification since it takes into account the minor phases such as gypsum, anhydrite, and hemihydrate and differentiates between the polymorphism varieties of cement phases (M1 alite, M3 alite, β belite, and γ belite). However, it was shown that Bogue calculation remains a primary estimation method of only the major clinker phases (C3S, C2S, C3A, and C4AF). Only for calcite amount must be better estimated by thermogravimetric technique or calcimetry method than Rietveld method, since there is an overlapping of the peaks of calcite and alite.

In-depth mineralogical quantification of MSWI bottom ash phases and their association with potentially toxic elements

Municipal solid waste incineration bottom ash fractions ≤4 mm are the most contaminated ones in terms of potentially toxic elements (PTEs). In order to estimate potential environmental impacts, it is important to understand the association of the PTEs with the mineral phases. Large area phase mapping (SEM/EDX) using “PhAse Recognition and Characterization - PARC” software in combination with quantitative X-ray powder diffraction has been used to characterize amorphous and crystalline BA phases for the first time. The results show that one of the main incineration products was melilite and an amorphous phase with a melilitic composition. The ratio of crystalline to amorphous melilite was 1:2. They formed an inhomogeneous layer around BA particles and contained a high percentage of the PTEs, i.e., Cu, Zn, Ni and Cr. Other major sources of PTEs (especially Ni and Cu) were iron oxides produced during incineration and the weathering products, such as calcite and ettringite (Cu and Zn). After extensive characterization of BA, a sequential extraction procedure (SEP) was performed, which exposed bottom ash to different chemical environments designed to dissolve specific phases and release their PTEs into solution. The extracted solutions and solid residues generated from the extraction procedure were analyzed to identify the association between PTEs and dissolved phases of BA. By combining SEP results with information obtained via large area phase mapping it is shown that SEP can be used for studying the association of PTEs with the phase that cannot be investigated with XRD/EDX, such as organic matter and Fe-Mn-hydrous oxides. Furthermore, according to SEP results a high percentage (40–80 wt%) of each investigated PTE can be considered immobile and not susceptible to leaching in the environment.

Fish Bone as a Source of Raw Material for Synthesis of Calcium Phosphate

Fish bone is rich in calcium carbonate, which makes it an alternative source of low cost calcium carbonate for the synthesis of calcium phosphate bioceramic for use in bone regeneration. The calcium phosphate bioceramic was prepared by a wet precipitation method with acid and base reactions. The synthesized bioceramic was characterized in terms of X-ray diffraction (XRD), scanning electron microscopy (SEM/EDS), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTRI), average crystallite size and refinement by the Rietveld method for the quantification of crystalline phases. The results indicated the formation of a biphasic calcium phosphate bioceramic comprising 67.6 % of β-calcium pyrophosphate (β-CPP) and 32.1 % of β-tricalcium phosphate (β-TCP). This biphasic calcium phosphate bioceramic synthesized using fish bone waste presented nanostructured nature with an average crystallite size of 69.58 nm, which is very promising for biomedical applications.