Fracture of Inoculated Iron Under Biaxial Stresses

1955 ◽  
Vol 22 (2) ◽  
pp. 172-174
Author(s):  
I. Cornet ◽  
R. C. Grassi
Keyword(s):  
Cast Iron ◽  
Stress Concentration ◽  
Stress Concentration Factor ◽  
Concentration Factor ◽  
Gray Cast Iron ◽  
Energy Criterion ◽  
Gray Cast ◽  
Published Data ◽  
Thin Wall ◽  
As Stress

Abstract Data are presented on the fracture of inoculated-iron thin-wall tubes, investigated under various ratios of axial to tangential stress, ranging from pure tension to pure compression. These data are consistent with published data on gray cast iron. It may be assumed that in cast-iron, plates of friable graphite in an iron matrix, act like solid iron with respect to compressive stresses, but they act as stress-concentrating cavities with respect to tensile stresses. This gives a stress-concentration factor, which is easily determined experimentally. Stress-concentration factors obtained were 3.2–3.3 for gray cast iron, and 2.4–2.5 for inoculated cast iron. A distortion-energy criterion for fracture, modified by this stress-concentration factor, is consistent with the experimental data. It appears that the concentration of the dispersed graphite, and the shape and size of this brittle phase, affect the fracture strength under combined stresses.

The Flow and Fracture of a Brittle Material

1950 ◽  
Vol 17 (3) ◽  
pp. 233-248
Author(s):  
L. F. Coffin
Keyword(s):  
Cast Iron ◽  
Stress Concentration ◽  
Stress Concentration Factor ◽  
Concentration Factor ◽  
Gray Cast Iron ◽  
Gray Cast ◽  
Residual Tensile Stress ◽  
Two Dimensional ◽  
Combined Stress ◽  
Plastic Stress

Abstract The mechanism of flow and fracture of a gray cast iron can be understood if one considers the microstructure to consist of a ductile structure with a random dispersion of cracks due to the graphite flakes following the concept of Fisher. A notch effective stress can be calculated for a critically situated crack by a knowledge of the external stresses, a plastic stress-concentration factor of 3, and a residual tensile stress at the sharp edge of the crack, based upon either the “maximum-shear” theory or the “distortion-energy” theory. This allows the formulation of generalized plastic stress-strain relationships and renders gray cast iron applicable to the many known solutions for plastic flow of ductile metals. Fracture in the region of tension-tension and tension-compression can be evaluated by a similar analysis, using the same stress-concentration factor and the same residual stress. A combined stress-testing program is described wherein thin-walled cast-iron tubes are subjected to two-dimensional states of combined stress covering the complete two-dimensional field.

The Thermal Fatigue Performance for Cast Iron Brake Drum of Large Trucks

2011 ◽  
Vol 117-119 ◽  
pp. 821-823
Author(s):  
Gao Lu ◽  
Wen Yan Wang ◽  
Jing Pei Xie
Keyword(s):  
Cast Iron ◽  
Stress Concentration ◽  
Crack Initiation ◽  
Thermal Fatigue ◽  
Stress Concentration Factor ◽  
Concentration Factor ◽  
Fatigue Crack Initiation ◽  
High Strength ◽  
Fatigue Properties ◽  
Brake Drum

This paper studies the application in different cast iron brake drum the thermal fatigue properties of materials. The results show that the stress concentration factor of grey cast iron, hot fatigue crack initiation, low intensity, and easy to expand, organization crack initiation poor stability, antioxidant ability is poor, thermal fatigue is poorer. 35% of vermicular cast iron and of ductile iron high strength, toughness, good stress concentration factor small, thermal fatigue is well.

Research of Properties and Microstructure on High-Strength Casting of Turbo-Charger

2011 ◽  
Vol 328-330 ◽  
pp. 1292-1296
Author(s):  
An Xia Pan
Keyword(s):  
Cast Iron ◽  
Gray Cast Iron ◽  
Continuous Production ◽  
High Strength ◽  
Intermediate Frequency ◽  
Gray Cast ◽  
Thin Wall ◽  
Test Results ◽  
Thin Walls ◽  
Turbo Charger

Combining with productive practice, production of intermediate castings in high-strength turbochargers under the condition of intermediate frequency furnaces is analysed in this paper. By adopting measures of compound inoculation and increasing Sulfur, 95% type A graphite and high-strength intermediate castings whose tensile strength is 300 MPa are acquired. Furthermore, moderate amounts of S and Mn as well as CE values are determined according to test results. As for thin-wall gray cast iron with high strength and complicate structure, whenwSis low andwCis high, castings with good graphite form can be produced. But it is not stable and the strength is low. Adding inoculants like Calballoy and Si-Ca-Ba can significantly improve the graphite form on the edge of thin-walls. WhenwCis stabilized at about 4.1, stable and continuous production of high strength gray cast iron with good graphite form can be guaranteed by adding sulfur and controlling the amount of Mn. The proportion of A type graphite and that of pearlite are both more than 90%.When high-strength gray cast iron is produced in intermediate frequency furnaces,wSshould be controlled between 0.1% and 0.12% andwMnshould be controlled between 0.5% and 0.55%.

Fracture of Gray-Cast-Iron Tubes Under Biaxial Stresses

1949 ◽  
Vol 16 (2) ◽  
pp. 178-182
Author(s):  
R. C. Grassi ◽  
I. Cornet
Keyword(s):  
Cast Iron ◽  
Tangential Stress ◽  
Gray Cast Iron ◽  
Gray Cast ◽  
Thin Wall ◽  
Pure Tension ◽  
Similar Materials ◽  
Pure Compression ◽  
Stress Ratios

Abstract The fracture of gray-cast-iron thin-wall tubes was investigated, for various ratios of axial to tangential stress ranging from pure tension to pure compression, yielding data for some stress ratios not previously reported. Analysis of the results reveals that the present theories of fracture do not account completely for the data obtained, thus indicating the need for further investigations of similar materials.

Teknologi Inokulasi Besi Cor Kelabu FC-250 Untuk Mencegah Pengerasan Pada Dove Tale Produk Ragum Tipe 125

2019 ◽  
Vol 16 (2) ◽  
Author(s):  
Amin Suhadi ◽  
Seodihono
Keyword(s):  
Mechanical Properties ◽  
Cast Iron ◽  
Treatment Process ◽  
Gray Cast Iron ◽  
Spare Parts ◽  
Gray Cast ◽  
Micro Structure ◽  
Control Factors ◽  
Seed Inoculation ◽  
Casting Industry

Production technology of metal casting industry in Indonesia needs to be improved, especially in the manufacturing of spare parts and box engine made of gray cast iron which has various wall thick such as dove tale construction. Microstructure of gray cast iron is influenced by cooling rate during casting, chemical composition and melting treatment process (inoculation). The part which has the thinnest thickness has the fastest cooling therefore, the grain boundary is smaller compared to other section. As a result this part has highest hardness and difficult to be machined. This research is conducted to solve this problem by modifying melting and solidification treatment process. The research starting from micro structure analysis, composition and mechanical properties tests on the product, and then conducting modification treatment through Taguchi method approach. Experimental results obtained show that the best level settings to control factors which affect to the uniformity of the microstructure and mechanical properties in gray cast iron is the addition of seed inoculation super ® 75, as much as 0.25% with the method of inoculation material entering into the Transfer Ladle.Teknologi produksi pada industri pengecoran di Indonesia masih membutuhkan perbaikan terutama dalam pembuatan komponen mesin perkakas dan peralatan pabrik yang terbuat dari besi tuang kelabu yang mempunyai variasi ketebalan yang besar seperti konstruksi ekor burung (dove tale). Pada pengecoran, struktur mikro dari besi tuang kelabu sangat dipengaruhi oleh kecepatan pendinginan, komposisi kimia dan proses perlakuan pada logam cair (inokulasi). Bagian yang mempunyai ukuran paling tipis mempunyai kecepatan pendinigan paling tinggi karena itu ukuran butirnya jauh lebih kecil dari bagian lain, akibatnya bagian ini mempunyai kekerasan lebih tinggi dan sulit dilakukan pengerjaan mesin. Penelitian ini bertujuan untuk memperbaiki hal ini yang terjadi pada dove taledengan cara memodifikasi proses perlakuan pada cairan besi dan proses pendinginan. Penelitian dimulai dari analisa struktur mikro, pengujian komposisi kimia, pengujian sifat mekanis pada produk kemudian dilakukan modifikasi menggunakan pendekatan metode statistik Taguchi. Hasil penelitian menunjukkan bahwa pengaturan terbaik yang dapat diperoleh untuk mendapatkan keseragaman struktur mikro dan sifat mekanis pada pengecoran besi tuang kelabu adalah penambahan seed inoculation super ® 75, sebesar 0.25% dengan metode pemasukan inokulasi kedalam Ladle pengangkut logam cair.Keywords: carbon, micro structure, hardness, inoculation

MEEHANITE GF-20

Alloy Digest ◽  
1973 ◽  
Vol 22 (2) ◽  
Keyword(s):  
Fracture Toughness ◽  
Corrosion Resistance ◽  
Shear Strength ◽  
Cast Iron ◽  
Physical Properties ◽  
Surface Treatment ◽  
Tensile Properties ◽  
Gray Cast Iron ◽  
Heat Treating ◽  
Gray Cast

Abstract MEEHANITE GF-20 is a gray cast iron designed principally for high machinability and is used where strength is not an important factor. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and shear strength as well as fracture toughness and fatigue. It also includes information on corrosion resistance as well as casting, heat treating, machining, joining, and surface treatment. Filing Code: CI-39. Producer or source: Meehanite Metal Corporation.

ISO 185/JL/225

Alloy Digest ◽  
2020 ◽  
Vol 69 (9) ◽  
Keyword(s):  
Tensile Strength ◽  
Cast Iron ◽  
Gray Cast Iron ◽  
Heat Treating ◽  
International Organization ◽  
Gray Cast ◽  
Damping Capacity ◽  
Lower Strength ◽  
Test Pieces ◽  
Lower Carbon

Abstract ISO 185/JL/225 is an intermediate-tensile-strength gray cast iron that has a predominantly pearlitic matrix, and a tensile strength of 225–325 MPa (33-47 ksi), when determined on test pieces machined from separately cast, 30 mm (1.2 in.) diameter test bars. Compared with the lower strength gray cast iron grades, ISO 185/JL/225 contains lower carbon and silicon contents, while still maintaining excellent thermal conductivity, damping capacity, and machinability. This datasheet provides information on composition, physical properties, tensile properties, and compressive strength as well as fatigue. It also includes information on heat treating. Filing Code: CI-73. Producer or source: International Organization for Standardization (ISO).

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