Case hardened steel

Case-based reasoning CA. See Cyanuric acid Case-hardened steels Case hardening... 

Gas used as a fumigant for citrus trees, and in ships and buildings against rodents and vermin salts used for case-hardening steel Possesses a peculiar peach blossom odor nausea and vomiting feeble pulse shallow breathing dyspnea cyanosis convulsions and collapse... 

Diffusion layers of transition metal nitrides are (similar to case hardened steels, which should not be discussed here) prepared by heating metals and alloys in nitrogen or ammonia, occasionally diluted with an inert gas. Mainly titanium and... 

TanakaR, Morishita H, YongchuanL, Hosokawa A, UedaT, Purumoto T (2009) Cutting tool edge temperature in finishing hard turning of case hardened steel. Key Eng Mater 407-408 538-541... 

Self-tapping inserts. Fig. 14.4(a), cut their own threads, are available in brass, case-hardened steel and stainless steel from M3 to M16 and are used in the more brittle thermoplastics and in thermosets. 

Carburizing n. A process for case-hardening steels in which the objects to be hardened are heated with carbonates and charcoal in the absence of air for bout 24 h at 840-950° C, then quenched in oil. The depth of hardening is about 1.7 mm and the surface hardness is from 50 to 55 on the Rockwell C scale. 

Moulds are made from steel, aluminium and sometimes from solid polyurethane or silicone rubber or occasionally glass-reinforced plastic (polyester or epoxy resins). For long life, case-hardened steel is very satisfactory. Air vents are recommended as OT mm (0 004 in) between horizontal mould plates. 

As we have already noted, this gearbox originally used steel ears. These were noisy and costly. They were made from case-hardened steel and there was chatter, especially when they became worn or damaged, resulting in wear on the back flanks of the teeth. They also required external lubrication, which can be a nuisance in an office environment. 

Hardened steels and tempered alloys Case-hardened steels... 

The case-hardening steels may be divided into three general classes, depending on the hardenabihty of the core ... 

Low-carbon steels cover a range of steels with carbon content up to 0.3%. These cannot be hardened by direct heating and quenching, but can be case-hardened. Steels containing 0.2% to 0.25% carbon, referred to as mild steels, are used in lightly stressed applications and can be readily machined and welded. They are used for general engineering purposes as bar, plate, sheet and... 

For reasons mentioned previously, the molds are made of case hardened steel or a fully coated material with a hardened or refined surface and tough core. All components that do not have molding surfaces and are exposed to wear are made of steel with strengths from 600 to 700 N/mm. Hard chrome plating or a corrosion-resistant material has to be selected to protect the finish and the molding surfaces against wear caused by friction and chemical attack. 

The structure is manufactured from pre-hardened mold steel such as 1.2312 or from a corrosion-resistant steel 1.2085, while the splits are available in different materials. Here, case-hardening steels and depth-hardened steels such as 1.2343 are available. 

Type Non-alloyed mold steel Corrosion resistant case hardening steel Corrosion resistant heat treated stainless steel Standard case hardening steel Heat treated mold steel... 

Example of use Mold frame steel Mold frame steel Case hardening steel, mold frame steel... 

Pre-hardened plastic mold steels (hardness -31 HRC) Hardened plastic mold steels (hardness -62 HRC) Case hardening steels (hardness -62 HRC) Surface finished steels (700-3500 HV)... 

FIGURE 3.10 Core Strength of case-hardening steels 1.2162 and 1.2767 as a function of diameter and quenching process... 

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