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Introduction
Published in Vipulkumar Ishvarbhai Patel, Qing Quan Liang, Muhammad N. S. Hadi, Concrete-Filled Stainless Steel Tubular Columns, 2019
Vipulkumar Ishvarbhai Patel, Qing Quan Liang, Muhammad N. S. Hadi
Austenitic stainless steels are the most commonly used stainless steels in engineering structures, designated as grades 304, 316, 304L, and 316L. The grades 304L and 316L are the low carbon variants of grades 304 and 316. These stainless steels contain 18% chromium and 8% nickel in their chemical composition. The chromium content of the grade 316 austenitic stainless steel is slightly lower than that of the grade 304 one, but grade 316 stainless steel contains an additional 2% molybdenum to increase its resistance against corrosion. Grades 304L and 316L austenitic stainless steels have a maximum of 0.03% carbon, which greatly reduces the residual stresses induced from the welding process. Austenitic stainless steels have good corrosion resistance and high ductility, are easily fabricated in different shapes, and readily weldable. These stainless steels become stronger by cold working but not by the heat treatment. The mechanical properties of austenitic stainless steels are given in Tables 1.1 and 1.2. It can be seen from Tables 1.1 and 1.2 that the strengths of austenitic stainless steels are comparable to carbon steels.
Engineering Control of the Aseptic Filling Environment
Published in Kenneth E. Avis, Sterile Pharmaceutical Products, 2018
The most commonly used material for machines in aseptic applications is stainless steel. It has strength, hardness, durability, and dimensional stability that makes it perform well in mechanical and structural situations, and the right grades will resist corrosion. The most commonly used grades of stainless steel are the 18-8 alloys (18 percent Cr, 8 percent Ni), which include type 302 (general purpose), 303 (free machining), and 304 (clean welding). These have good corrosion resistance against many acids and other corrosives, but are not impervious to all chemical attacks. Grade 316 stainless steel, with a higher nickel content, is the most resistant to corrosion of the commercial stainless steel alloys, and will withstand formaldehyde, peracetic acid, hydrogen peroxide, and other corrosive sanitizing agents. Therefore, 316 stainless steel is the grade of choice in a clean room (Clark and Varney 1962, 325–328). Grade 304 is more resistant to chlorine, however. For welded components it is important to use a stainless steel with 0.3 percent or less carbon content, to avoid intergranular corrosion at the weld boundaries (Smith 1986, 676–677).
Minimisation of carbon emission regarding surface roughness and processing time during turning process of medium carbon steel and stainless steel materials
Published in Australian Journal of Mechanical Engineering, 2023
Yusuf Tansel Ic, Ebru Saraloğlu Güler, Turgut Şaşmaz
Figure 10 shows the optimisation results that are obtained by MINITAB. Table 11 lists the results for minimum carbon emission, experiment time and surface roughness correspond to the parameters with levels 2, 2, 3, 2.3 and 5.7 for spindle speed, cutting speed, depth of cut, type of cutting tool, and work-piece material. Value of 2.3 indicate that the working material can be selected as 303 or 316 grade stainless steel. However, AISI 303 is more convenient due to its alloying elements. The alloying elements affect the machinability of the working material. Furthermore, the high machinability decreases both of the responses that are carbon emission and machining time (Liu et al. 2016). Therefore, the correlation between machinability and the satisfaction of the responses of the study can be constructed. It is known that the amount of sulphur and manganese in AISI 303 grade is higher than that of AISI 304 grade (Akasawa et al. 2003). Sulphur incorporation in the steel increases machinability so the cutting force is decreased (Akasawa et al. 2003; Gandarias et al. 2008). In addition, it was claimed that the machinability of AISI 303 grade is higher than both of grades 304 and 316 (“Machinability Comparison Chart,” n.d). Moreover, molybdenum can be responsible for grade 316 not being the best candidate. Since molybdenum is incorporated in grade 316 (Gandarias et al. 2008), the machinability is decreased (Krolczyk, Nieslony, and Legutko 2015).
Evaluation of elastomer–plastomer vulcanised modifiers for using as bitumen binder modifier
Published in International Journal of Pavement Engineering, 2022
Mahmoudreza Favakeh, Saeed Bazgir, Morteza Karbasi, Mohammad Zia Alavi, Ali Abdi
Modified bitumen binders with 2%, 4%, and 6% (by weight of the base binder) were produced using German-made IKA6000 high shear mixer in a vessel, with a volume of 250 ml, immersed in a silicon oil bath. The mixing vessel was made for this study out of stainless steel grade 316 and four baffles were embedded to create and intensify the turbulence motion during the blending process (Figure 2). The 60/70 base bitumen was heated up to 150°C before the incorporation of the EPV modifier. The EPV was added gently within 15 min, while the temperature of bitumen increased to 180°C and the mixing speed increased to reach 3200 rpm. The mixing was then continued for two hours at 180°C at the speed of 3200 rpm. It is worth to mention that the mixing temperature, time and speed were chosen to ensure polymer particles were well interacting with a bitumen binder and uniformly dispersed.
An improved algorithm to predict the mechanical properties of nuclear grade 316 stainless steel under elevated-temperature liquid sodium
Published in Journal of Nuclear Science and Technology, 2021
Yaonan Dai, Xiaotao Zheng, Jiuyang Yu
As the most promising generation IV nuclear reactors, the sodium-cooled fast reactor (SFR) have got great significance in the application of nuclear power plants due to its high efficiency, energy saving and safety characteristics [1–4]. Under high temperature environments (up to 823 K), SFR uses liquid sodium coolant to improve the efficiency of uranium resource utilization and reduce the generation of nuclear waste [5]. In order to ensure the structural integrity of the reactor components and achieve the design life of SFR up to 60 years, it is particularly important to study the change of sodium on the mechanical properties of reactor core materials [6]. At present, the core components of SFR mainly use nuclear grade 316 stainless steel (316SS, 316 H SS and 316LN SS, et al.) [7]. However, the review of the sodium corrosion experiment of nuclear grade 316SS revealed that the mechanical performance parameters of nuclear grade 316SS obtained in elevated-temperature liquid sodium are very limited. Hence, it is necessary to establish an efficient and accurate model to predict mechanical properties of nuclear grade 316SS based on the limited actual data.