Forging property, processing map, and mesoscale microstructural evolution modeling of a Ti-17 alloy with a lamellar (α+ß) starting microstructure.

This work identifies microstructural conversion mechanisms during hot deformation (at temperatures ranging from 750 °C to 1050 °C and strain rates ranging from 10-3 s-1 to 1 s-1) of a Ti-5Al-2Sn-2Zr-4Mo-4Cr (Ti-17) alloy with a lamellar starting microstructure and establishes constitutive formulae for predicting the microstructural evolution using finite-element analysis. In the α phase, lamellae kinking is the dominant mode in the higher strain rate region and dynamic globularization frequently occurs at higher temperatures. In the ß phase, continuous dynamic recrystallization is the dominant mode below the transition temperature, Tß (880~890 °C). Dynamic recovery tends to be more active at conditions of lower strain rates and higher temperatures. At temperatures above Tß , continuous dynamic recrystallization of the ß phase frequently occurs, especially in the lower strain rate region. A set of constitutive equations modeling the microstructural evolution and processing map characteristic are established by optimizing the experimental data and were later implemented in the DEFORM-3D software package. There is a satisfactory agreement between the experimental and simulated results, indicating that the established series of constitutive models can be used to reliably predict the properties of a Ti-17 alloy after forging in the (α+ß) region.

Detwining in Mg alloy with a high density of twin boundaries.

To investigate the role of preexisting twin boundaries in magnesium alloys during the deformation process, a large number of {10-12} tensile twins were introduced by a radial compression at room temperature before hot compressive tests with both low and high strain rates. Unlike the stable twins in Cu-based alloys with low stacking fault energies, {10-12} twins in Mg alloy are extremely unstable or easy to detwin through {10-12}-{10-12} re-twinning. As a result, non-lenticular residual twins and twin traces with misorientation of 5°-7° were present, as confirmed by electron backscatter diffraction. The extreme instability of the twins during compression indicates that both twin and detwinning require extremely low resolved shear stresses under our experimental conditions.

Effect of Multiple Reverse Transformation Treatments on Grain Refinement and Mechanical Properties of Biomedical Co-Cr-Mo-N Alloys Fabricated by Electron Beam Melting.

We investigated the improvement of mechanical properties of biograde Co-28Cr-6Mo-0.11N alloy prepared by electron beam melting through grain refinement via multiple reverse transformations. While the effects of single and double reverse transformation treatments on the microstructure have been investigated in previous studies, we investigated the effects of multiple reverse transformation heat treatments. The particle size was refined to 1/4, and the yield strength, tensile silence strength, and elongation were enhanced to 655 MPa, 1234 MPa, and 45%, respectively, satisfying ASTM F75 standards. Moreover, a mixed phase of ε and γ was observed to provide higher yield strength than a single γ structure. The dominant behavior in the γ → ε phase transformation at 1073 K was obvious. Grain growth was suppressed by the grain-boundary pinning effect of the Cr2N phase during reverse transformation to the γ phase. Because no fracture was caused by precipitates such as σ, η, and Cr2N phases, the influence of the precipitates on the tensile properties was small.

[Efficacy and toxicity of lapatinib plus capecitabine therapy in HER2-positive metastatic breast cancer].

We retrospectively investigated the efficacy and toxicity of lapatinib plus capecitabine in 45 HER2-positive breast cancer patients. The median number of treatment courses was 6(1-22). Brain metastasis developed in 18 cases(40%), and 19 cases(42.2%)had received previous capecitabine treatment for metastatic breast cancer. The objective response rate(ORR=CR+PR)was 22.2%(10/45), and clinical benefit rate(CR+PR+long SD=24w)was 46.7%(21/45).The median time to progression(TTP)was 24.9 weeks(95% CI: 15.2 -34.6 ), and the median overall survival(OS)was 78.1 weeks(95% CI: 55.7 -100.5)in all 45 cases. The median TTP was significantly longer in patients who had not received capecitabine previously(30 vs 16 weeks, 95% CI: 16.3 -43.7, p=0.0051 ). There was no statistical difference in median OS associated with previous capecitabine exposure(42.7 weeks, 95% CI: 21.4 -64, p=0.057 ). The median TTP was significantly longer in patients who received less than 2 treatment regimens with trastuzumab for MBC rather than 3 regimens more(27.3 vs 16 weeks, p=0.0257 ), but there was no statistical difference in median OS(81 vs 40.9 weeks, p=0.26 ). Lapatinib in combination with capecitabine is likely more useful in patients who are naive to capecitabine, who received less than two regimens for metastatic breast cancer.

The significance of thermomechanical processing on the cellular response of biomedical Co-Cr-Mo alloys.

Strengthening of biomedical Co-Cr-Mo alloys has been explored via thermomechanical processing for enhancing the durability of their biomedical applications. However, the effects of cold and hot deformation on the cellular activity continue to be unclear. In this study, we prepared Co-Cr-Mo alloy rods via cold swaging and hot-caliber rolling and studied the relationship between the microstructure and cellular response of pre-osteoblasts. The cold-swaged rod experienced strain-induced martensitic transformation, which increased the volume fraction of the hexagonal close-packed (hcp) ε-martensite to ∼60 vol.% with an increase in area reduction (r) to 30%. The 111γ fiber texture of the face-centered cubic (fcc) γ-matrix followed the Shoji-Nishiyama orientation relationship with ε-martensite. Cell culture results revealed beneficial effects of cold swaging on the cell response, in terms of adhesion, proliferation and morphology of cells, although increasing r did not significantly affect cellular metabolism levels. The addition of small content of Zr (0.04 wt.%) led to enhanced focal adhesion of cells, which became more significant at higher r. The microstructural evolution during hot-caliber rolling, namely, grain refinement without any phase transformation and strong texture development, did not appreciably affect the cellular activity. These findings are envisaged to facilitate alloy design and microstructural optimization for favorable tuning the osseointegration of biomedical Co-Cr-Mo alloys.

Smoke Suppression in Electron Beam Melting of Inconel 718 Alloy Powder Based on Insulator-Metal Transition of Surface Oxide Film by Mechanical Stimulation.

In powder bed fusion-electron beam melting, the alloy powder can scatter under electron beam irradiation. When this phenomenon-known as smoking-occurs, it makes the PBF-EBM process almost impossible. Therefore, avoiding smoking in EBM is an important research issue. In this study, we aimed to clarify the effects of powder bed preheating and mechanical stimulation on the suppression of smoking in the powder bed fusion-electron beam melting process. Direct current electrical resistivity and alternating current impedance spectroscopy measurements were conducted on Inconel 718 alloy powder at room temperature and elevated temperatures before and after mechanical stimulation (ball milling for 10-60 min) to investigate changes in the electrical properties of the surface oxide film, alongside X-ray photoelectron spectroscopy to identify the surface chemical composition. Smoking tests confirmed that preheating and ball milling both suppressed smoking. Furthermore, smoking did not occur after ball milling, even when the powder bed was not preheated. This is because the oxide film undergoes a dielectric-metallic transition due to the lattice strain introduced by ball milling. Our results are expected to benefit the development of the powder bed fusion-electron beam melting processes from the perspective of materials technology and optimization of the process conditions and powder properties to suppress smoking.

Mechanical Analysis of Notch-Free Pre-Bent Rods for Spinal Deformity Surgery.

STUDY DESIGN: Experimental study of spinal rod as per the American Society for Testing Materials (ASTM) F2193 methodology for static and dynamic four-point bending. OBJECTIVE: The hypotheses underlying this study were that the notch-free, curved rod would have a significantly higher ultimate load and fatigue strength compared with conventional notched curved rods. This study aimed to analyze the mechanical properties of notch-free curved rods compared with conventional notched rods. SUMMARY OF BACKGROUND DATA: The goal of instrumented spinal fusion in the management of spinal deformities is to realign the spine and maintain the correction and stability in order to obtain arthrodesis. Although rod curvature could play an important role, intraoperative contouring of the straight rod induces notches into the rod, leading to decreased fatigue strength. METHODS: Commercially produced titanium alloy (ϕ6.0 mm) and cobalt chromium alloy (ϕ5.5 mm) spinal rods were assessed by four-point bending tests in accordance with the ASTM F2193. RESULTS: Static four-point bending tests for the curved spinal rods showed that cobalt chromium alloy rods had significantly higher stiffness compared with titanium alloy rods. Notch-free cobalt chromium alloy rods had a significantly higher ultimate load than the conventional notched cobalt chromium alloy and titanium alloy rods. The dynamic four-point bending test showed that force/displacement at a minimum force at 2,500,000 cycles was larger in the notch-free cobalt chromium alloy rod than in the notched cobalt chromium alloy rod. CONCLUSION: The notch-free curved cobalt chromium alloy rod is likely to maintain its curvature after spinal deformity surgery with a decreased risk of breakage and could overcome the problems of the conventional notched rod such as breakage and spring-back. LEVEL OF EVIDENCE: N/A.

Favorable modulation of osteoblast cellular activity on Zr-modified Co-Cr-Mo alloy: The significant impact of zirconium on cell-substrate interactions.

Cobalt-chromium-molybdenum alloys exhibit good mechanical properties (yield strength: ~530 MPa, ultimate tensile strength: ~1114 MPa, elongation-to-failure: ~47.3%, and modulus: ~227 GPa) and corrosion resistance. In recent years, from the perspective of osseointegration, they are considered to be lower in rank in comparison to the widely used titanium alloys. We elucidate here the significant and favorable modulation of cellular activity of Zr-modified Co-Cr-Mo alloys. The average grain size of Co-Cr-Mo alloy samples with and without Zr was 104 ± 27 and ~53 ± 11 µm, respectively. The determining role of small addition of Zr (0.04 wt. %) to the Co-Cr-Mo alloys in favorable modulation of cellular activity was accomplished by combining cellular biology and materials science and engineering. Experiments on the influence of Zr addition to Co-Cr-Mo alloys clearly demonstrated that the cell adhesion, spread and cell-substrate interactions were enhanced in the presence of Zr. The spread/growth rate of cells was ~120% on the Co-Cr-Mo alloy and 190% per day on the Co-Cr-Mo-Zr alloy. While the % area covered by the cells increased from ~5.1 to ~33.6% on Co-Cr-Mo alloy and ~19.2 to ~47.8% on Co-Cr-Mo-Zr alloy after 2 and 24 hr of incubation. Similarly, the cell density increased from ~1354 to ~3424 cells/cm2 on Co-Cr-Mo alloy and ~3583 to ~7804 cells/cm2 on Co-Cr-Mo-Zr alloy after 2 and 24 hr of incubation. Additionally, stronger vinculin focal adhesion contact and signals associated with actin stress fibers together with extracellular matrix protein, fibronectin, were noted.

Centrifugal granulation behavior in metallic powder fabrication by plasma rotating electrode process.

In recent years, spherical powders with no or minimal internal pores fabricated by the plasma rotating electrode process (PREP) have been highly recommended for powder-type additive manufacturing. Most research on PREP is aimed at establishing relationship between PREP parameters and powder size. However, almost no dedicated research on granulation behavior has been conducted so far. In the present study, PREP experiments of Ti64 and SUS316 alloys were carried out. Numerical modeling based on computational thermo-fluid dynamics was developed to analyze the granulation behavior. In particular, the roles of the additionally introduced gas blast and the morphology of the electrode end surface in fluid granulation were preliminarily investigated. The study showed that in addition to the electrode's rotating speed and diameter, manipulating the plasma arc current (i.e., the melting rate) could also be an effective way to control the PREP-powder size. According to the simulation, there were competing actions of the gas blast affecting the powder size. The gas blast created disturbance on the fluid and deepened the depression of the electrode end surface, which facilitated powder refinement. However, the cooling effect enhanced the fluid stability and hindered fluid granulation. The conclusions indicated the possibility of using various methods to manipulate PREP-powder size.

[A case of metastatic breast cancer with liver metastasis effectively treated with capecitabine and vinorelbine].

A 31-year-old woman with cancer of the right breast underwent surgery in 1996. Histological examination demonstrated a solid tubular carcinoma that was positive lymph node metastasis and hormonal receptor, but negative for HER2 expression. The patient underwent adjuvant therapy with CAF and tamoxifen. At the age of 40 years old, Multiple liver metastasis appeared to the patient. We treated her with paclitaxel. But multiple liver metastasis became progressive disease. Next we treated with capecitabine and vinorelbine. The liver metastasis reduced, and, in the eighth month, the liver metastasis disappeared after 9 cycles. We changed treatment to goserelin, and anastrozole. The period of complete response was 1 year 3 months.

Tuning strain-induced γ-to-ε martensitic transformation of biomedical Co-Cr-Mo alloys by introducing parent phase lattice defects.

In this study, we examined the effect of pre-existing dislocation structures in a face-centered cubic γ-phase on strain-induced martensitic transformation (SIMT) to produce a hexagonal close-packed ε-phase in a hot-rolled biomedical Co-Cr-Mo alloy. The as-rolled microstructure was characterized by numerous dislocations as well as stacking faults and deformation twins. SIMT occurred just after macroscopic yielding in tensile deformation. Using synchrotron X-ray diffraction line-profile analysis, we successfully captured the nucleation of ε-martensite during tensile deformation in terms of structural evolution in the surrounding γ-matrix: many dislocations that were introduced into the γ-matrix during the hot-rolling process were consumed to produce ε-martensite, together with strong interactions between dislocations in the γ-matrix. As a result, the SIMT behavior during tensile deformation was accelerated through the consumption of these lattice defects, and the nucleation sites for the SIMT ε-phase transformed into intergranular regions upon hot rolling. Consequently, the hot-rolled Co-Cr-Mo alloy simultaneously exhibited an enhanced strain hardening and a high yield strength. The results of this study suggest the possibility of a novel approach for controlling the γ → ε SIMT behavior, and ultimately, the performance of the alloy in service by manipulating the initial dislocation structures.

Osseointegration of 3D printed microalloyed CoCr implants-Addition of 0.04% Zr to CoCr does not alter bone material properties.

Electron beam melting (EBM) is a three-dimensional (3D) printing technique for the production of metal structures where complex geometries with interconnected porosities can be built. Incorporation of as little as 0.04% Zr into the CoCr alloy can significantly improve the biomechanical anchorage of constructs fabricated by EBM. Here we investigate bone material properties, including microstructure and composition, adjacent to 3D printed CoCr implants with and without addition of 0.04% Zr, after 8 weeks of healing in the rabbit femur. In low amounts, zirconium addition does not alter the microstructure and extracellular matrix composition of bone formed adjacent to the surface of EBM manufactured implants. Bone ingrowth into surface irregularities of 3D printed CoCr and CoCr + Zr implants is seen. Extensive remodeling is also evident. Osteocytes attach directly on to the implant surface. The interfacial tissue at CoCr and CoCr + Zr has similar mineral crystallinity, apatite-to-collagen ratio, carbonate-to-phosphate ratio, Ca/P ratio, bone-implant contact, percentage porosity, and osteocyte density (N.Ot/B.Ar). Compared to the native bone, the mineral crystallinity of the interfacial tissue was lower while N.Ot/B.Ar was higher for both CoCr and CoCr + Zr. Overall, the results indicate that bone tissue adjacent to CoCr and CoCr + Zr implants is highly mature and exhibits comparable healing kinetics. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1655-1663, 2018.

Impact of minor alloying with C and Si on the precipitation behavior and mechanical properties of N-doped Co-Cr alloy dental castings.

The addition of carbon and silicon as minor alloying elements was examined as a means to improve the mechanical properties of novel nitrogen-doped Co-Cr-based alloy dental castings. Samples of Co-32Cr-9W-Si-0.25N-C (mass%) alloys were prepared using a dental-casting machine. Microstructural analysis was performed on the alloys using scanning electron microscopy, electron-backscatter diffraction, electron-probe microanalysis, and X-ray diffraction, with a particular focus on the precipitation behavior. The findings were compared with thermodynamic predictions and examined in relation to the tensile properties and Vickers hardness at room temperature. All of the prepared alloys had a face-centered-cubic γ-phase matrix, with grains measuring a few millimeters in diameter and consisting of dendritic substructures. The precipitation of the intermetallic σ-phase, which occurred in the interdendritic regions with solidification segregation of Cr and W, was replaced with M23C6 through the addition of carbon. This significantly increased the ultimate tensile strength of the alloys without severe loss of ductility, although the 0.2% proof stress did not change. The addition of silicon, on the contrary, promoted the formation of the precipitates, which included M6C and the σ-phase, making the alloys brittle. The results of this study highlight the role of minor alloying elements, such as carbon and silicon, on the microstructural and mechanical properties; the findings also shed light on the significance of precipitation control in dental castings of Co-Cr alloys, which should aid the design of novel dental alloys.

Effect of nitrogen on the microstructure and mechanical properties of Co-33Cr-9W alloys prepared by dental casting.

The effect of nitrogen concentration on the mechanical properties of Co-33Cr-9W alloy dental castings fabricated using the "high-Cr and high-N" concept was investigated. Microstructural analysis was performed on the alloys, and findings were discussed in relation to the mechanical properties. Owing to their high nitrogen concentrations (0.25-0.35wt%), all alloys prepared exhibited face-centered cubic (fcc) γ-phase matrices with a-few-millimeter grains consisting of dendritic substructures. Strain-induced martensitic transformations to produce hexagonal close-packed (hcp) ε-phases were not identified under tensile deformation. The precipitation of the intermetallic σ-phase was identified at the interdendritic regions where solidification segregation of Cr and W occurred. The size and chemical composition of this σ-phase did not vary with the bulk nitrogen concentration. Adding nitrogen to the alloys did not alter their tensile yield stress or Vickers hardness values significantly, suggesting that the nitrogen strengthening effect is affected by the manufacturing route as well as local chemistry that is involved in the microstructural evolution during solidification. The tensile ductility, on the other hand, increased with an increase in nitrogen concentration; the alloy with 0.35wt% nitrogen exhibited 21% elongation with a high 0.2% proof stress (589MPa). This significant improvement in ductility was likely caused by the reduction in the amount of σ-phase precipitates at the interdendritic regions following the addition of nitrogen.

Serial Injections of Cryopreserved Fat at -196°C for Tissue Rejuvenation, Scar Treatment, and Volume Augmentation.

BACKGROUND: Fat grafting has become popular since the first report of structural fat grafting in 2001. Fat grafting is effective not only for volume augmentation but also for tissue revitalization. However, fat harvesting is necessary before fat grafting can be performed. Therefore, the performance of serial fat injections is very challenging when treating such patients. METHODS: From August 2015 to March 2017, we investigated 219 patients who underwent fat grafting using the fat that had already been cryopreserved at -196°C. RESULTS: Follow-up ranged from 3 months to 2 years. No complications occurred, and all outcomes were satisfactory. Three representative cases were also reviewed. CONCLUSIONS: The cryopreserved fat at -196°C could be served as a useful method for serial fat grafting for clinical use; however, further research involving longer follow-up and pathological findings are needed.

Nitinol powders generate from Plasma Rotation Electrode Process provide clean powder for biomedical devices used with suitable size, spheroid surface and pure composition.

The nickel-titanium alloy (57Ni-43Ti in wt%) was atomized by the plasma rotating electrode process (PREP). The PREP parameters such as plasma arc current, rotating electrode speed with corresponding PREP powder size range in weight percentage analysis, powder morphology and biocapability of cells were studied by scanning electron microscopies, Inductively Coupled Plasma and X-ray diffraction techniques. From the electrode of the produced powders, the composition has no obviously changes. Weight percentage up to 31.8% of the range under 300 µm while the rotation electrode speed increase to 12k rpm. Spherical and flat with smooth surface were observed in different size range. Brittle phase was not observed of XRD data. The nitinol powder has high biocapability with cells showed no cytotoxicity and well cell adhesion in the in vivo assay.

Ultrasound Diagnosis and Treatment of Breast Lumps after Breast Augmentation with Autologous Fat Grafting.

BACKGROUND: Breast augmentation with autologous fat has been performed in Japan for over 30 years. However, complications include breast lumps and oil cysts. Such breast lumps greatly reduce patient satisfaction, and are currently difficult to diagnose and treat for many cosmetic surgery clinics. This study aimed to elucidate the effectiveness of ultrasound diagnosis and treatment of patients with breast lumps after breast augmentation with autologous fat grafting. METHODS: We used diagnostic and therapeutic ultrasound to examine 256 patients with breast lumps between April 2012 and April 2017. We determined the nature, size, and location of the maximal lump. Breast lumps were classified into five types: cystic, complex, solid, calcification, and unclassifiable. The method of treatment (including fine-needle aspiration, VASER liposuction, lumpectomy, and extended lumpectomy) was selected according to the lump type, and the efficacy of treatment was determined by postoperative palpation and ultrasound. RESULTS: A total of 198 patients (198/256, 77%) requested treatment. Cystic lumps (79/256, 31%) were treated by fine-needle aspiration. VASER liposuction was used to treat complex (64/256, 25%) and solid lumps (50/256, 19%). Calcification (58/256, 23%) and unclassifiable lumps (5/256, 2%) were removed via periareolar incision. There were no serious complications. In all cases, the lumps were no longer palpable after treatment, and ultrasound showed that they had either contracted or disappeared. CONCLUSIONS: The appropriate treatment for breast lumps after breast augmentation with autologous fat grafting must be selected according to the nature of the lumps. Ultrasound is essential for diagnosing the breast lump type and determining the best treatment.

Stacking-fault strengthening of biomedical Co-Cr-Mo alloy via multipass thermomechanical processing.

The strengthening of metallic biomaterials, such as Co-Cr-Mo and titanium alloys, is of crucial importance to the improvement of the durability of orthopedic implants. In the present study, we successfully developed a face-centered cubic (fcc) Co-Cr-Mo alloy with an extremely high yield strength (1400 MPa) and good ductility (12%) by multipass hot-rolling, which is suitable for industrial production, and examined the relevant strengthening mechanisms. Using an X-ray diffraction line-profile analysis, we revealed that a substantial increase in the number of stacking faults (SFs) in the fcc γ-matrix occurred at a greater height reduction (r), while physical modeling demonstrated that the contribution of the accumulated SFs (i.e., the reduction in SF spacing) with an increase in r successfully explains the entire strengthening behavior of the hot-rolled alloy. The present study sheds light on the importance of the SF strengthening mechanism, and will help to guide the design and manufacturing strategy for the high-strength Co-Cr-Mo alloys used in highly durable medical devices.

Effects of carbon addition on wear mechanisms of CoCrMo metal-on-metal hip joint bearings.

The wear behaviors of biomedical CoCrMo prosthetic alloys containing various amounts of carbon were investigated using a standard hip joint simulator in a simulated body fluid. A few chunks and punctate σ-phase precipitates were observed in the low-carbon (LC) alloy; these were responsible for the abrasion and run-in wear. Increasing the carbon content led to greater precipitation of globular M23C6-type carbides. As a result, lower wear loss was observed in the high-carbon (HC) alloy. However, the Student's t-test analysis on wear loss indicated that there was no significant difference in wear loss between the LC-LC and HC-HC combinations. Surface fatigue caused by torn-off of Mo-rich carbides was the dominant wear mechanism in the HC alloy. Further, Cr-rich carbides prevent three-body abrasion and increase the wear resistance.

Developing high strength and ductility in biomedical Co-Cr cast alloys by simultaneous doping with nitrogen and carbon.

There is a strong demand for biomedical Co-Cr-based cast alloys with enhanced mechanical properties for use in dental applications. We present a design strategy for development of Co-Cr-based cast alloys with very high strength, comparable to that of wrought Co-Cr alloys, without loss of ductility. The strategy consists of simultaneous doping of nitrogen and carbon, accompanied by increasing of the Cr content to increase the nitrogen solubility. The strategy was verified by preparing Co-33Cr-9W-0.35N-(0.01-0.31)C (mass%) alloys. We determined the carbon concentration dependence of the microstructures and their mechanical properties. Metal ion release of the alloys in an aqueous solution of 0.6% sodium chloride (NaCl) and 1% lactic acid was also evaluated to ensure their corrosion resistance. As a result of the nitrogen doping, the formation of a brittle σ-phase, a chromium-rich intermetallic compound, was significantly suppressed. Adding carbon to the alloys resulted in finer-grained microstructures and carbide precipitation; accordingly, the strength increased with increasing carbon concentration. The tensile ductility, on the other hand, increased with increasing carbon concentration only up to a point, reaching a maximum at a carbon concentration of ∼0.1mass% and decreasing with further carbon doping. However, the alloy with 0.31mass% of carbon exhibited 14% elongation and also possessed very high strength (725MPa in 0.2% proof stress). The addition of carbon did not significantly degrade the corrosion resistance. The results show that our strategy realizes a novel high-strength Co-Cr-based cast alloy that can be produced for advanced dental applications using a conventional casting procedure. STATEMENT OF SIGNIFICANCE: The present study suggested a novel alloy design concept for realizing high-strength Co-Cr-based cast alloys. The proposed strategy is beneficial from the practical point of view because it uses conventional casting approach-a simpler, more cost-effective, industrially friendly manufacturing process than other manufacturing processes such as thermomechanical processing or powder metallurgy. The developed alloys showed the excellent strength-ductility balance and significantly high strength comparable to that of wrought Co-Cr-Mo alloys, while maintaining acceptable ductility and good corrosion resistance. We described the relationship between microstructures and mechanical and corrosion prosperities of the developed alloys; this provides the fundamental aspect of the proposed strategy and will be helpful for further investigations or industrial realization of the proposed strategy.