ISO 185/JL/300

JSA FC300 is a higher-tensile-strength gray cast iron that has a pearlitic matrix, and a minimum tensile strength of 300 MPa (44 ksi), when determined on test pieces machined from separately cast, 30 mm (1.2 in.) diameter test bars. The tensile strength of JSA FC300 approaches the maximum tensile strength attainable in gray cast iron. It provides a combination of high strength while still maintaining good thermal conductivity. Applications, therefore, tend to be confined to those where thermal conductivity requirements in service preclude the use of one of the other higher-strength materials such as spheroidal graphite cast irons, which have inferior thermal properties. This datasheet provides information on composition, physical properties, hardness, and tensile properties. It also includes information on casting and heat treating. Filing Code: CI-97. Producer or source: Japanese Standards Association (JSA).

Since ductile cast iron was invented, cast iron has been used for various purposes. However, because of its poor corrosion resistance, the use of cast iron in corrosive environments was restricted. As pre-viously reported, the authors succeeded in obtaining a prominent protective film on steel by silicon impregnation (so-called siliconizing).In the present work, 3 kinds of specimens, i.e. nodular cast irons having ferrite and pearlite matrix, respectively, and gray cast iron, were siliconized by means of a mixed gas of silicon tetrachloride and oxygen free argon in accordance with the silicon impregnation of steel. The results obtained were summarized as follows.(1) Microscopic examination showed that porous films were formed on nodular cast iron with ferrite matrix, and particularly, on gray cast iron. On the contrary, when nodular cast iron with pearlite matrix was siliconized at a relatively high temperature for a short time, the film obtained had comparatively less pores in number.(2) Immersion tests of the siliconized cast irons in dilute sulfuric acid showed that the siliconized film protected the underlying cast iron core from the attack of acid though it was porous. Above all, the film which had been formed on nodular cast iron with pearlite matrix by siliconizing at a high temperature for a short time showed the best corrosion resistance.

The influence of nitriding on the fatigue resistance of grey and nodular (ductile) cast iron piston rings was studied for six chemical compositions. The selected materials include three grey cast irons: one with a mixed initial microstructure (martensite plus bainite), the second martensitic and another martensitic alloyed with niobium; and three nodular cast irons: one common nodular cast iron, the second alloyed with Nb and another alloyed with Al and V. These materials were gas nitrided for 3 and 6 h. The relationship between the mechanical behaviour and the treatment time (depth of nitrided layer) was established. Samples were tested under a cyclical bending load. The stresses were determined in the cross-section, where the biggest moment was experienced. Results were statistically treated by means of Weibull analysis. Nitriding showed that fatigue resistance of grey cast iron with a martensitic structure is higher than that of a mixed structure. Fatigue resistance of nodular cast irons is red...

A note on the effect of nodularization characteristics on the workability of quenchp-hardened and tempered cast irons

The nitriding process can be effectively applied to steel with alloying elements. The higher the alloying element in the steel maximizes the mechanical properties, including hardness. However, the raw material can be costly, therefore using cheap materials (without alloys) is a challenge in increasing surface hardness through iron nitride formation. Furthermore Grey and nodular cast iron have different properties and characteristics in the structure. This research focuses on the ability of the cast-iron structure to affect the nitride layer formation. Gas nitriding was conducted in a fluidized bed reactor with a 550°C in 20 % N2 and 80 % NH3 atmosphere at a flow rate gasses of 0.7 m3/hr process temperature and holding for 2, 4, and 6 hours. Tests are conducted by observing the depth of hardening, SEM, and EDAX. According to the results, the nitriding process increases the surface hardness of cast iron. The highest hardness value is nodular cast iron with a holding time of 6 hours (345 HV) and a hardening depth of up to 20-micron meters. The compounds formed in the nitride layer include FeN, Fe2-3N, Fe4N, and Fe2N. The compound formed is strongly influenced by the treatment time. Furthermore, the comparison of nitriding treatment on gray and nodular cast iron was influenced by the flake and nodule structure. In general, the nodule structure is responsible for maximum hardness. The longer treatment time allows the nitrogen atoms to diffuse more to the surface, while the flake structure limits the absorption of nitrogen atoms into the surface of the cast iron. Characterization of Nodular Cast Iron shows that The hardening depth distribution trend due to the nitriding process in nodular cast iron was not much different from gray cast iron.

Effects of single-pass laser heat treatment on erosion behavior of cast irons

Water main failures are very expensive for municipalities because they typically result in expenses associated with repair costs, flood damage, and loss of revenue to affected businesses. Water main failures also interrupt the operation of vital services, such as medical care and fire-fighting operations. Currently, millions of dollars are spent annually by the water utility industry and by municipalities on the repair of failed components of the water distribution infrastructure, such as components that are made from gray cast iron or "gray iron” pipe and ductile cast iron or "ductile iron” pipe. The rate of municipal water main failures is expected to increase as the existing cast iron infrastructure continues to age. The cost of repairing damages caused by broken water mains (and subsequent flooding damage) may become an important item in many municipal budgets. It is important to develop a corrosion program to prevent catastrophic failures of water mains. This paper presents a plan consisting of several phases including preassessment, indirect assessment, direct assessment, and integrity assessment of failed water mains. We will elaborate on the failure mechanisms, failure analysis protocols, and corrosion mitigation strategies for water mains that experience breaks. Water main breaks are mainly due to corrosive soil, pipe material, galvanic action, stray current corrosion, or microbiological induced corrosion (MIC). This paper provides an overview of corrosion issues commonly experienced by water main pipes, presents specific case histories involving graphitic corrosion, galvanic corrosion, stray current corrosion, and MIC. In this paper, we will introduce a graphitization sensor for condition assessment of water mains. This sensor can identify the location and extent of graphitization on water main.

This paper presents the results of constant load low-cycle rotating bending fatigue tests that were carried out on nodular cast iron and grey cast iron with the speed of stress repetition at 10 and 100rpm. The deflection values of specimens (vertical and horizontal deflections) were monitored and recorded during the tests. All tests were conducted at room temperature.The results obtained are summarized as follows:(1) The low-cycle fatigue process of the nodular cast iron and the grey cast iron can be expressed by the horizontal and vertical deflections.(2) Under the low-cycle rotating bending tests, the relations between N and σa/σB for both the nodular cast iron and the grey cast iron can be given by almost the same straight line on the logarithmic scale coordinates. (N: number of cycles to failure, σa: stress amplitude, σB: tensile strength.)

The microstructure and properties of gray cast iron are closely related. For gray cast iron with pearlite matrix, adjusting graphite characteristics to improve casting performance is the most effective method. It is of great significance to analyze the relationship between graphite characteristics and properties of gray cast iron for the development of gray cast iron with high tensile strength and high thermal conductivity. Regression models of graphite characteristics and properties of gray cast iron was established, including tensile strength and thermal conductivity. By calculating the coefficients of the two models, the different effects of graphite characteristics on the properties of gray cast iron were obtained. By testing the regression models, the feasibility of the regression analysis method in the performance analysis of gray iron castings was determined. According to the analysis results, some improvement schemes are put forward to improve the performance of castings.

With the global shift in energy structure and the advancement of the "double carbon" strategy, methanol has gained attention as a clean low-carbon fuel in the engine sector. However, the corrosion-wear coupling failure caused by acidic byproducts, such as methanoic acid and formaldehyde, generated during combustion severely limits the durability of methanol engines. In this study, we employed a systematic approach combining the construction of a corrosion liquid concentration gradient experiment with a full-load and full-speed bench test to elucidate the synergistic corrosion-wear mechanism of core friction pairs (cylinder liner, piston, and piston ring) in methanol-fueled engines. The experiment employed corrosion-resistant gray cast iron (CRGCI), high chromium cast iron (HCCI), and nodular cast iron (NCI) cylinder liners, along with F38MnVS steel and ZL109 aluminum alloy pistons. Piston rings with DLC, PVD, and CKS coatings were also tested. Corrosion kinetic analysis was conducted in a formaldehyde/methanoic acid gradient corrosion solution, with a concentration range of 0.5-2.5% for formaldehyde and 0.01-0.10% for methanoic acid, simulating the combustion products of methanol. The results showed that the corrosion depth of CRGCI was the lowest in low-concentration corrosion solutions, measuring 0.042 and 0.055 μm. The presence of microalloyed Cr/Sn/Cu within its pearlite matrix, along with the directional distribution of flake graphite, effectively inhibited the micro-cell effect. In high-concentration corrosion solutions (#3), HCCI reduced the corrosion depth by 60.7%, resulting in a measurement of 0.232 μm, attributed to the dynamic reconstruction of the Cr2O3-Fe2O3 composite passive film. Conversely, galvanic action between spherical graphite and the surrounding matrix caused significant corrosion in NCI, with a depth reaching 1.241 μm. The DLC piston coating obstructed the permeation pathway of formate ions due to its amorphous carbon structure. In corrosion solution #3, the recorded weight loss was 0.982 mg, which accounted for only 11.7% of the weight loss observed with the CKS piston coating. Following a 1500 h bench test, the combination of the HCCI cylinder liner and DLC-coated piston ring significantly reduced the wear depth. The average wear amounts at the top and bottom dead centers were 5.537 and 1.337 μm, respectively, representing a reduction of 67.7% compared with CRGCI, where the wear amounts were 17.152 and 4.244 μm. This research confirmed that the HCCI ferrite-Cr carbide matrix eliminated electrochemical heterogeneity, while the DLC piston coating inhibited abrasive wear. Together, these components reduced the wear amount at the top dead center on the push side by 80.1%. Furthermore, mismatches between the thermal expansion coefficients of the F38MnVS steel piston (12-14 × 10-6/°C) and gray cast iron (11 × 10-6/°C) resulted in a tolerance exceeding 0.105 mm in the cylinder fitting gap after 3500 h of testing. Notably, the combination of a HCCI matrix and DLC coating successfully maintained the gap within the required range of 50-95 μm.

This study presents an analysis of the abrasive effects of sediments from the bed of the Acre River, Brazil, on the wear of three different ferrous materials employed in the manufacture of impellers of centrifuge pumps used to catch raw water. In order to evaluate the abrasive wear and specific wear coefficient (k) as a function of sediment concentration, tests were conducted in samples of SAE 8620 steel, nodular cast iron and gray cast iron by using a rotary-ball abrasion meter. These tests employed abrasive slurry with concentration of 1, 2, 3, 5 and 10 g L-1 of sediments in distilled water. The volume of worn material as a function of the relative velocity of water flow in relation to the impeller blades was mathematically estimated. The experimental results showed that: i) The semi-angular and semi-rounded shapes of the sediments from the Acre River produced evidence of micro-grooving and plastic deformation in the three metallic alloys; ii) SAE 8620 steel showed higher resistance to abrasive wear than samples of gray and nodular cast iron; iii) the increase in the volume of worn material due to increment in sediment concentration and the relative velocity of the mixture (water + sediment) to the rotor pads.

The interphase boundaries in gray and ductile cast iron were studied with a scanning Auger microprobe (SAM). Sulfur and oxygen were found to be adsorbed at the flake/ metal interfaces in the gray iron, while the nodule/metal and intercrystalline graphite interfaces in the ductile iron were free of foreign elements. The only magnesium detected in the magnesium modified ductile iron was combined with phosphorus and sulfur as a compound. A model is presented which proposes that Fe−C−Si eutectic alloys in the absence of surface active impurities (such as in vacuum casting of high purity materials) produce nodular graphite due to the inherent instability of the graphite/melt interface. The sulfur and oxygen always present in commercial alloys adsorb at the graphite/melt interface, effectively “stabilizing” the active sites on the graphite basal planes, and preventing spherulitic growth. The purpose of modifiers is to getter these impurities.

BACKGROUND: The paper discusses the issues of improving the quality of piston-type hydraulic machines. The base case is the mud pump. The service purpose of the mud pump is to supply mud. The main problem that occurs when operating hydraulic machines of this type is increased wear of the working surfaces of the cylinder sleeves. This is mainly due to the presence of fractions in the drilling mud, which have increased abrasive properties. To increase the durability of the assembly, high-chromium alloyed cast irons of the IChKh-22 type are used as a material for making the sleeve. However, these parts are expensive. It should also be noted that high-quality cast iron has worse foundry properties compared to other types of cast iron (for example, gray cast iron). AIM: Evaluation of the possibility of improving the quality of piston-type hydraulic machines by improving the design of the cylinder assembly. METHODS: To improve the quality of piston-type hydraulic machines, it is proposed to use gray cast iron, which is hardened by heating in contact with a mixture of oxides of alloying elements. Considering the fact that quality is a complex property, it is reasonable to evaluate it based on a comparison of both technical and economic aspects. The complex assessment was carried out using a differential method based on technical and economic indicators: tightness of the connection of the “sleeve-rod” pair, wear rate of the surface layer of the cylinder sleeve, strength, rigidity and cost. The tightness and wear were determined by calculation using experimental data on the properties of the hardened layer, and the strength and stiffness of the bushings were determined using the finite element method. RESULTS: The results obtained show that the proposed variant is not inferior to the basic one in terms of wear resistance and tightness, and is significantly more efficient in terms of cost. Analysis of the options was carried out without taking into account technological aspects such as processing performance and the percentage of defects. As a perspective for further research, these criteria should also be looked at. CONCLUSION: In the course of the research, it was found that the working part of the sleeve, which is made of alloy cast iron, can be replaced with modified gray cast iron. As a result of the assessment of the quality level, it was found that the resulting quality indicator for the proposed option is higher than for the basic one. Although the specific quality indicators characterizing the functional purpose for modified cast iron are somewhat lower, the economic effect of using such bushings is significantly higher than its counterpart. Thus, the resulting indicator characterizing the quality of bushings in general for modified gray cast iron significantly exceeds its analogues.

In this paper, sliding friction and wear behaviors of gray cast iron A35 and white cast iron manufactured by quenching from the same cast iron in water were studied and compared by employing pin-on-disk wear tests. Microstructure of the worn surfaces before and after the wear tests were investigated by optical microscope observations. These images show that flakes separated from the surface in gray cast iron due to delamination process, while in white cast iron, the separation of materials from its surface is in the form of powder. In addition, the gray cast iron had higher graphite volume fraction with Type-A graphite flake morphology. The results show that white cast iron has less rate of wear than gray cast iron due to the higher hardness. However, gray cast iron because of presenting graphite flakes in its surface (lubricant property) has lower average coefficient of friction.

The old gray cast iron for water supply pipes in Yokohama City which was made in the UK in 1887 is highly corrosion resistant. The corrosion behavior of the old gray cast iron in soils was studied. For comparison, a gray cast iron used for modern pipes, a spheroidal graphite cast iron, and a carbon steel were tested. The corrosion potentials and corrosion rates were measured. The corrosion products and the base metals were analyzed by X-ray diffractometry and energy dispersion spectroscopy. The corrosion rate of the gray cast iron made in the UK in 1887 was lower than those of the others. The gray cast iron contains a large amount of steadite, which is a ternary eutectic (γ-Fe, Fe 3 C, and Fe 3 P). The network structure of steadite enclosed the corrosion products and decreased the corrosion rate.