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About Journal
Journal: Chinese Journal of Rare Metals
Establishment year: 1977
Administrator: China Association for Science and Technology
Sponsor: The Nonferrous Metals Society of China;
China GRINM Group Co., Ltd.
Publisher: Youke Publishing Co., Ltd
Periodicity: Monthly
Tel:010-82241917/82240869
E-mail:rmchina@263.net
ISSN:0258-7076
CN:11-2111/TF
Chinese Journal of Rare Metals is a comprehensive journal, published monthly in Chinese, administrated by China Association for Science and Technology, and sponsored by The Nonferrous Metals Society of China and China GRINM Group Co., Ltd. Academician Haili Tu is the Editor-in-Chief. Chinese Journal of Rare Metalis included by American Engineering(EI compendex), the important database SCOPUS...(Details)
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In order to protect the right of readers and authors and to maintain the quality and reputation of this journal, Chinese Journal of Rare Metals will test and screen each manuscript strictly in the process of publication. The manuscript will be rejected and punished seriously if it is identified as academic misconduct. The specific testing process and treatment methods are as follows:
1. This journal adopts academic misconduct detection system of CNKI for automatic detection, and the China Literature Journals Full-text Database is used as the comparative database, which test academic misconduct behaviors such as paper copy and plagiarism, forgery, tampering, improper attribution, a draft casting two or more journals, etc.
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3. The criteria of the manuscript identified as academic misconduct are as follows:
1) The manuscript content copies intact or basically from other achievements.
2) The content of the paper that changes the type of others’ achievement or does not change the type but changes the specific forms of others’ achievements which are protected by copyright and use it as their own independent complete works;
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4. The treatment methods of identified academic misconduct papers:
1) The editorial department treats the paper eventually identified as academic misconduct prudently, and informs authors timely, allowing authors to explain and defend for this issue before making a treatment decision;
2) If the paper is already received but has not been officially published, we will notify the author that the paper will be directly treated as rejected paper in the manuscript-handling process and the employment qualification will be canceled. In addition, the author is given criticism education and warning ;
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5) For authors who are accused of serious plagiarism or cast their paper in multiple journals as the first author, our publication will not accept their papers in 2 years;
5. The treatment of the dissent of authors:
If authors disagree with the identification and treatment results of our journal, they can put forward the application of recheck to the editorial department literally (inadmissible overdue). The editorial department will invite experts to re-review those papers and then make the final decisions. Authors will be informed in 30 working days.
The above provision will be put into force from the date of release and the editorial department of Chinese Journal of Rare Metals is responsible for the interpretation.
Hot Deformation Behavior of Ti80G Titanium Alloy in Two-Phase Region and Microstructure Characteristics
Li Shuchang;Zhang Hui;Luo Dengchao;Song Xiaoqing;Xu Jianwei;Dai Yi;Zeng Weidong;Ti80G titanium alloy is a newly developed near-α alloy derived from Ti80 titanium alloy, exhibiting high strength, good toughness, weldability, and excellent corrosion resistance, with potential applications in petroleum drilling and marine engineering. To investigate its hot deformation behavior and microstructural evolution in the α+β two-phase region, isothermal uniaxial compression tests were conducted using a Gleeble-3500 thermomechanical simulator at 850 and 900 ℃ with a constant strain rate of 0.1 s-1. A height reduction of 50% was applied at both temperatures, while reductions of 25%, 50%, and 75% were employed at 900 ℃. The deformed specimens were immediately water-quenched and characterized by scanning electron microscopy and electron backscatter diffraction. The flow behavior of Ti80G titanium alloy showed pronounced temperature sensitivity. The flow stress increased rapidly at the initial stage, reached a peak, and subsequently decreased toward a relatively stable level, reflecting the competition between work hardening and dynamic softening. Increasing the deformation temperature from 850 to 900 ℃,The decrease in flow stress was mainly associated with enhanced dislocation motion and dynamic softening at elevated temperature together with the increased fraction of the more deformable β phase. After deformation, the microstructure consisted mainly of retained primary α grains and secondary α colonies formed from the β matrix. At a height reduction of 50%, the fraction of primary α phase, decreased from approximately 42% to 7% while its average grain size decreased from approximately 9 to 4 μm as the temperature increased from 850 to 900 ℃, indicating enhanced dissolution of the primary α phase. At 900 ℃, increasing the height reduction mainly changed the morphology and spatial distribution of the primary α phase. At 75% reduction, the primary α grains were markedly flattened and preferentially aligned perpendicular to the compression direction.Reconstruction of prior grains showed that the mean minimum deviation from the ideal Burgers orientation relationship increased from 3.2 to 6.8 with increasing temperature and from 4.5° to 7.5° as the height reduction increased from 25% to 75%, indicating that both temperature and deformation affected the α/β crystallographic relationship. Increasing the temperature from 850 to 900 ℃ decreased the mean kernel average misorientation (KAM) from 0.79° to 0.62° and the fraction of low-angle grain boundaries from 52.7% to 21.4%, while increasing the recrystallized fraction from 7.61% to 16.0%. These changes indicated that elevated temperature facilitates dislocation rearrangement and annihilation and promoted dynamic recrystallization. At 900 ℃, the recrystallized fraction decreased from 24.6% at 25% reduction to 16.0% at 50% reduction and subsequently increased to 28.4% at 75% reduction. Meanwhile, the mean KAM decreased to 0.51° at 75% reduction, indicating enhanced dynamic recrystallization and microstructural softening under large deformation.
Titanium Alloy Powders Modified with Copper Metal and Their Microstructure and Properties of Composites
Wang Guopeng;Xu Shanna;Liu Le;Xu Junjie;Li Mingjia;Sun Guodong;Dong Longlong;TC4 titanium alloy is an α+β dual-phase titanium alloy with excellent comprehensive properties, including high specific strength, hardenability and low elastic modulus. Hence, it has been widely used in aviation, aerospace, automotive, biomedical and other fields. With the rapid development of aerospace industry, there are higher requirements for the performance of Ti alloy materials. Particles dispersion strengthened Ti matrix composites(TMCs) has received widespread attention owing to their excellent interfacial bonding strength and superior mechanical properties. However, due to the hard brittleness of ceramic particles, ceramic particles will lead to a decline in the ductility of TMCs, which would limit their application. Compared with ceramic particles, metal particles have exhibited a good ductility and good bonding with Ti alloy metal matrix. Cu is a β-stabilizing element that reduces the β-transus temperature in Ti alloy. According to the equilibrium phase diagram of Ti-Cu binary alloy, Ti2 Cu intermetallic compound would precipitate during densification and sintering. The size and morphologies of Ti_2Cu can be further adjusted through hot deformation and heat treatment process, which has a significant effect on its mechanical properties. The uniform distribution of reinforcements in the matrix is the prerequisite for obtaining TMCs with excellent properties. Generally, the low energy ball milling process is adopted to introduce the micro/nano scale reinforcements on the surface of titanium alloy powder, however ball milling treatment usually grinds the metal with good ductility into pieces(such as Cu powders), resulting in uneven distribution on titanium alloy powders and difficult to control the thickness. On the other hand, electroless plating to modify titanium alloy powder will cause uneven distribution of modified reinforcement on the surface of titanium alloy and serious pollution of the reagent used, which is not good for the purity of titanium alloy composite powder. In order to evenly disperse Cu on the surface of spherical TC4 powder without introducing impurity elements, Cu metallized modified titanium alloy shell structure composite powder(Cu@TC4) was firstly synthesized using magnetron sputtering technology, and then in-situ Ti_2Cu-reinforced TC4 matrix composites were fabricated using spark plasma sintering(SPS) technology. The effects of plating parameters on the powder morphologies and microstructure evolution of sintered composites were systematically investigated using scanning electron microscope(SEM), transmission electron microscope(TEM), and X-ray diffractometer(XRD) diffractometer. Cu contents in the composite powders were measured using inductively coupled plasma emission spectrometer(ICP). Furthermore, the tensile properties of the fabricated composites were tested using universal electronic testing machine at room temperature. The results showed that Cu was evenly coated on the surface of TC4 powders. Cu contents in the mixtures powder increased gradually with an increasing of sputtering power, whereas with the bias increased gradually, Cu contents in the composite powder showed little difference. When the magnetron sputtering power increased from 100 to 300 W, and Cu contents in the composite powder increased from 0.28% to 1.06%. XRD results showed that not only α-Ti but also Cu phases could be detected in the composite powder after Cu plating, and the diffraction peak of Cu phase was gradually enhanced with the increase of sputtering power, the main reason was attributed to the gradual increase of Cu content. When the sputtering power was 100 W, XRD only detected α-Ti in the sintered samples, and with the increase of sputtering power, Cu content in the composite powder increased, the in-situ Ti_2Cu gradually increased, and Ti_2Cu phase was gradually detected in the sintered samples. SEM analysis showed that after sintering at 1000 ℃, the as-sintered sample had dense structure without obvious defects(such as holes). The microstructure of composite was a typical Widmanstein structure owing to the α+β dual-phase titanium alloy cools slowly from a higher than β transition temperature. TEM analysis showed that there were many Ti_2Cu nanoparticles precipitated along the α/β phase boundary in Ti_2Cu/TC4 composites. The formation process of Ti_2Cu in TC4 matrix could be identified as: 1) After Cu plating on the surface of TC4 powder, Cu was evenly distributed on the surface of TC4 powder; 2) During sintering, Ti-Cu undergoes in-situreaction to generate Ti_2Cu nanoparticles and precipitation on β-Ti. When the magnetron sputtering bias was 0 V and the sputtering power was 300 W, the tensile strength and yield strength of Ti_2Cu/TC4 composite were(986.9±5.0) and(881.7±4.4) MPa, which were 9.4% and 11.8% higher than that of TC4 alloy, respectively. Nano-Ti_2Cu particles blocked the movement of dislocations in the matrix, played the role of second phase strengthening, and improved the tensile strength of the composite. The improvement of the strength of composites in this work could be attributed to the refining of α phase in the grain and the dispersion strengthening of Ti_2Cu nanophase. The room temperature tensile fracture had many dimples and tearing edges, showing typical mixed fracture characteristics. The research results would provide a reference for the preparation of Ti-based core-shell powders and a good balance between strength and ductility of TMCs.
Microstructure and Properties of Ultrafine-Grained Pure Copper Fabricated via ECAP
Yang Xirong;Yan Kun;Liu Xiaoyan;Wang Gengjie;Wang Junjie;Copper and its alloys are widely used in high-speed railways, electronic devices, and lead frames due to their good electrical and thermal conductivity, as well as their excellent corrosion resistance. The pure copper used in this study has high electrical conductivity and excellent ductility, and is widely used in high-speed railways, electronic devices, and lead frames. However, its relatively low strength also limits its application in structural components. Severe plastic deformation(SPD) is a processing technology that significantly refines the grains of materials by applying extremely high plastic strain. Through multiple or continuous deformation passes, high-density dislocations and shear bands are generated within the material, promoting grain refinement to the sub-micron or even nano level. Among many SPD methods, equal channel angular pressing(ECAP), as a typical SPD technique, involves extruding material through a channel with a specific angle to achieve severe(pure) shear deformation. ECAP has been widely used to refine the grain size of metallic materials to the sub-micron or nano level and is one of the most effective methods for preparing bulk ultrafine-grained materials.In this study, the subject was as-cast pure copper with a purity of 99.996%. The pure copper underwent multiple ECAP deformations at room temperature, with an internal die angle Φ of 90°and an external arc angle Ψ of 20°. Butter and graphite were used as lubricants, the press rod speed was 2.5 mm·s-1, the number of extrusion passes was 8, and the extrusion path was the C-path. Optical microscopy and electron backscatter diffraction(EBSD) were used for microstructural analysis of the samples. The study investigated the microstructure, grain size, dislocation density, and degree of deformation of the as-cast pure copper after each ECAP pass. The results showed that after ECAP deformation, the microstructure exhibited mutually parallel and interwoven band-like structures. As the number of deformations passes increased, the bands thinned and gradually transformed into equiaxed grains. The as-cast pure copper exhibited large equiaxed grains with an average size of 89.5 μm. After the first pass of ECAP deformation, the grains were elongated and fragmented into band-like structures. These bands were oriented parallel to the shear direction and had an average width of approximately 17 μm. With increasing deformation passes, the band structures became finer and more uniform. After 4 passes, the bands were further refined, with an average width of about 2.7 μm, and some regions exhibited a more equiaxed morphology. By the 8 th pass, the microstructure consisted predominantly of equiaxed grains with an average size of 4.24 μm. The increase in dislocation density played a significant role in the strengthening of the material. The dislocation density increased dramatically with each pass of ECAP deformation, reaching a peak after 4 passes. The dislocation density increased from 2.9×1014 to 31.24×1014 m-2, a 997.24% increase compared to the original as-cast pure copper. Vickers hardness tester was used to measure the microhardness of the surface of each sample. The hardness reached a peak of HV 178.24 after 4 passes of ECAP deformation, indicating significant work hardening. The hardness of the pure copper after 8 passes of ECAP deformation was slightly lower at HV 173.6. A digital direct current(DC) low resistance tester was used to measure and calculate the electrical conductivity, with five measurements taken and averaged. The electrical conductivity of the material was also affected by ECAP deformation. As the grain size decreased and the dislocation density increased, the electrical conductivity decreased. The initial electrical conductivity of the ascast pure copper was 96.34%IACS, which decreased to 81.22%IACS after 8 passes of ECAP deformation. This reduction in electrical conductivity was attributed to the increased scattering of electrons by dislocations and grain boundaries, which impede the flow of electric current. A universal testing machine was used to conduct constant-speed room-temperature tensile tests on samples in different states, with a tensile speed of 0.37 mm·min-1. Each group of experiments was conducted twice to ensure the accuracy and reproducibility of the results for subsequent comparative analysis. The tensile strength reached a peak of 588.19 MPa after 4 passes of ECAP deformation, and the yield strength reached 617 MPa. The yield strength was theoretically calculated using the rule of mixtures, with the strengthening increment from ECAP deformation expressed as the sum of the initial material strength, dislocation strengthening increment, and grain refinement strengthening increment. Calculations based on these increments yielded results that were in good agreement with the experimental data. Additionally, a nonlinear fitting formula for the relationship between the number of deformations passes and the yield strength was obtained by fitting the yield strength curve. ECAP process was highly effective in refining the grain size of pure copper and significantly improving its mechanical properties. Four passes of ECAP could achieve a relatively optimal balance between strength(588.19 MPa) and conductivity(81.22%IACS), providing a process reference for the industrial application of high-strength and high-conductivity pure copper. Future work should focus on optimizing ECAP process parameters to further enhance the balance between strength and electrical conductivity, potentially leading to new applications for pure copper in industries where both properties are critical.
Microstructure and Resistance Property of Cu-8Mn-nSi Alloy
Wang Bing;Ma Zhixin;Li Defu;Zou Honghui;Wen Junguo;With the development of science and technology, Cu-Mn precise resistance alloy has extremely important applications in the fields of national defense, military industry, aerospace, 5G communication, and artificial intelligence due to its advantages such as low production cost, low temperature-coefficient of resistance(TCR) and low thermoelectric potential compared to pure copper. However, because of the existence of the “K-state” structure, the resistance temperature curve of Cu-Mn precise resistance alloy is close to a parabola, which makes it difficult to further reduce the temperature coefficient of resistance of the Cu-Mn alloy. Therefore, how to weaken or eliminate the “K-state” through the combination of alloying and heat treatment process, and finally reduce the TCR has always been the focus of Cu-Mn precision resistance alloy. The effects of Si element and annealing temperature on microstructure and resistance performance of Cu-Mn precise resistance alloy are studied by optical microscope, direct current(DC) resistance tester, and resistance temperature coefficient tester. The first is element composition design. According to the principle of resistivity superposition of solid solution and the binary phase diagram of Cu-Mn, Mn-Si and Cu-Si alloys, the chemical composition of Cu-8Mn-n Si alloys were designed. The second is the preparation of samples. Cu-8Mn-n Si(n=0, 1.6, 2.2, 3.0; %, mass fraction) alloys with a diameter of Φ12 mm were prepared by horizontal continuous casting, and then the alloys were drawn to Φ2.5 mm. The cumulative deformation of the cold drawing process was 96%. The drawn Cu-8Mn-n Si alloys were annealed at 600 ℃ for 1 h to obtain annealed Cu-8Mn-n Si(n=0, 1.6, 2.2, 3.0; %, mass fraction) alloy samples. Cu-8Mn-2.2 Si alloy with a diameter of Φ2.5 mm was annealed at 550, 600, 650 and 700 ℃ for 1 h to obtain annealed Cu-8Mn-2.2 Si alloy samples with different annealing temperatures. All the annealed alloys were pickled in an acid solution to remove the surface oxide. Finally, the microstructure, resistivity, and temperature coefficient of resistance of these samples were observed and tested by optical microscope(OM), scanning electron microscope(SEM), DC resistance tester, and resistance temperature-coefficient tester. The results showed that the addition of Si could increase the resistivity of Cu8Mn alloy. When the Si content was 0～3.0%, the resistivity of the alloy increased with the increases of Si content, from 0.26 to 0.42 μΩ·m. After adding 3.0% Si to Cu-8Mn alloy, the alloy resistivity increased by about 61.5%. The resistivity of Cu-8Mn-2.2Si alloy increased first and then decreased as annealing temperature increases, with a maximum value of 0.35 μΩ·m at 650 ℃. In terms of the temperature coefficient of resistance, when 2.2% Si was added to Cu-8Mn alloy, TCR decreased from 21.74×10-6 to-3.20×10-6 ℃-1, which showed that Si element could reduce TCR of Cu-8Mn alloy. However, as the Si content continued to increase to 3.0%, the temperature coefficient of resistance increased. Therefore, TCR of Cu-8Mn-n Si(n=0, 1.6, 2.2, 3.0; %, mass fraction) alloy had a minimum value at the Si content of 2.2%. TCR of Cu-8Mn-2.2Si alloy increased with the increase of annealing temperature, from-18×10-6 to 87.3×10-6 ℃-1. It indicated that the annealing temperature had a significant effect on TCR of Cu-8Mn-2.2Si alloy. When the annealing temperature was 600 ℃, TCR of the alloy was close to zero, which was-3.20×10-6 ℃-1. In terms of microstructure, When Si content was 0, 1.6% and 2.2%, the alloys were dominated by equiaxial grains with a small number of twins, and the grain size of the alloys was 9.75, 9.66 and 9.13, respectively. The grain size was maintained at about 9.5, that was, the Si content had little effect on the grain size of the alloy. When the Si content was 2.2%, a small number of second phase particles precipitated at the grain boundaries of the Cu-8Mn-2.2Si alloy. As the Si content increased to 3.0%, the second phase particles precipitated increased. After heat treatment of Cu-8Mn-2.2Si alloy, the second phase particles gradually dissolved into the matrix, and the average grain size increased with the increase of heat treatment temperature, from 7.08 to 22.96 μm. In Cu-8Mn-n Si(n=0, 1.6, 2.2, 3.0; %, mass fraction) alloy, Si element could reduce the temperature coefficient of resistance of Cu-8Mn alloy. When Si content was 2.2%, TCR of the alloy was close to zero. According to the thermodynamic analysis of Cu-Mn-Si alloy, compared with the thermodynamic binding force of Mn and Cu, Mn and Si had a stronger thermodynamic binding force. The Si element could change the diffusion thermodynamics of Mn atoms, weaken the "K-state" thermodynamic process in Cu-8Mn alloy, and significantly reduce the alloy's TCR. TCR of Cu-8Mn-2.2Si alloy increased with the increase of annealing temperature. When the annealing temperature was 600 ℃, TCR of the alloy was close to zero, which was-3.20×10-6 ℃-1. Therefore, In the experimental range, the best Si content in Cu-8Mn-n Si(n=0, 1.6, 2.2, 3.0; %, mass fraction) precision resistance alloy was 2.2%, and the best annealing temperature was 600 ℃.
Microstructure and Mechanical Properties of Ni-Ni_3Si Eutectic In-Situ Composites with Different Solidification Rates
Li Wei;Cui Chunjuan;Liang Zhanpeng;Luo Lei;Su Haijun;As a high-temperature structural material that has attracted much attention, Ni_3Si intermetallic compound exhibits excellent high-temperature mechanical properties, good oxidation and corrosion resistance, and high specific strength. It shows great potential in aeroengine components and other high-temperature application fields. However, Ni_3Si intermetallic compound also has the characteristics of room temperature brittleness and low fracture toughness, which limits its industrial development and production. At present, the methods to improve the brittleness of intermetallic compounds include alloying, disordered treatment, grain refinement, heat treatment, directional solidification and so on. Among them, directional solidification technology can obtain grain structure or single crystal structure with specific orientation, and prepare materials with excellent properties. Ni-Ni_3Si eutectic in-situ composites were fabricated using directional solidification techniques, which combined the Ni matrix phase with high ductility with the brittle phase Ni_3Si, thus improving the brittleness of the intermetallic compound Ni_3Si. Ni-Si eutectic alloy ingots were prepared by vacuum induction melting technology according to Ni-Si binary alloy phase diagram. Then, directionally solidified Ni-Ni_3Si eutectic in-situ composites were prepared with rapid, uniform and stable solidification at the solidification rates of 25, 40 and 55 μm·s–1, respectively. The effect of solidification rate on the microstructure characteristics and mechanical properties was systematically studied. The microstructure and phase composition of Ni-Ni_3Si eutectic in-situ composites were analyzed by optical microscope(OM) and energy dispersive spectrometer(EDS). The volume fraction of eutectic phase and dendrite spacing were measured by image software Image J. Vickers hardness of Ni-Ni_3Si eutectic in-situ composites at different solidification rates was measured by HXD-2000x digital Vickers hardness tester. The test load was 4.903 N(500 gf) and the holding time was 15 s. The average hardness of 20 groups of each sample was measured. The compression test and three-point bending test of Ni-Ni_3Si eutectic in-situ composites were carried out at room temperature and high temperature(600 ℃) by electronic universal testing machine. At the same time, the fracture morphology was observed by Gemini SEM 300 field emission scanning electron microscope(SEM). The results showed that the solidification structure of Ni-Ni_3Si eutectic in-situ composites was composed of α-Ni matrix phase, Ni-Ni_3Si eutectic phase and Ni31Si12 metastable phase. The volume fraction of eutectic phase increased with the increase of solidification rate, and reaches 33.3% at 55 μm·s–1. The microstructure of Ni-Ni_3Si eutectic in-situ composites was refined, and the primary dendrite spacing and secondary dendrite spacing decreased with the increase of solidification rate. The experimental results were closest to the Trivedi model, close to the Ma model, and quite different from the Hunt-Lu model and the Kurz-Fisher model among the commonly used models for the correlation between the primary dendrite spacing and the solidification parameters. Therefore, the Trivedi model was more suitable for describing the primary dendrite arm spacing of Ni-Ni_3Si eutectic in-situ composites. The microhardness of Ni-Ni_3Si eutectic in-situ composites rose with the increase of solidification rate. The microhardness and primary dendrite spacing of Ni-Ni_3Si eutectic in-situ composites at different solidification rates conformed to the Hall-Petch formula. The microhardness increased with the decrease of dendrite spacing, and the relationship was as follows: HV=208.55+6.73λ–0.5. The microstructure of Ni-Ni_3Si eutectic in-situ composites became more uniform and gradually refined with the increase of solidification rate. Therefore, the compressive strength increased continuously under the same service temperature conditions, and the maximum compressive strain did not increase monotonically at room temperature. The compressive strength at room temperature and high temperature were 2512.28 and 1655.63 MPa when the solidification rate was 55 μm·s–1. The compression test of Ni-Ni_3Si eutectic in-situ composites at room temperature showed that the samples showed the characteristics of brittle fracture. There were cleavage steps, cracks and obvious fracture surfaces in the compression fracture at room temperature, indicating brittle fracture mode. It exhibited poor strength and good plasticity due to the softening effect of recovery and recrystallization when Ni-Ni_3Si eutectic in-situ composite was compressed to 70% deformation at high temperature. The compressed longitudinal section structure deformed in a direction perpendicular to the compression direction. The three-point bending test of Ni-Ni_3Si eutectic in-situ composites with varying solidification rates was carried out at the same temperature, and the bending strength of the material was improved compared with that of the as-cast material. The bending strength of Ni-Ni_3Si eutectic in-situ composite materials increased initially and then decreased as the solidification rate increased, reaching its maximum at a solidification rate of 40 μm·s–1. And the bending strength at room temperature and high temperature were 161.68 and 1045.11 MPa, respectively. The three-point bending fracture morphology of Ni-Ni_3Si eutectic in-situ composites at room temperature had cleavage steps and tearing edges, and the fracture mode was intergranular-trans crystalline mixed fracture. The plasticity of Ni-Ni_3Si eutectic in-situ composites at high temperature was better than that at room temperature, and the bending strength was greatly improved. The number of steps at the fracture was large, and the tearing area was pulled out, which was quasi-cleavage fracture.
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