Firstly, we shall look at the corrosion resistant alloys.
Within corrosion resistant alloys there are three main sub groups, B-alloys, C-alloys and G-alloys. Those Hastelloys® with high nickel and molybdenum have a high resistance to pitting and crevice corrosion, and those with high chromium percentages thrive in highly oxidizing environments.
Generally, C-alloys are the most versatile of all the Hastelloys®. Common to all C-type alloys are their ability to resist the formation of boundary precipitates in the weld heat-affected zone (inter-granular corrosion-weld decay). The most commonly used C-type alloy in industry is the C-276.
If we take a look at C-type alloys we see that Stainless Steel fails more often than Hastelloys® due to pitting and crevice corrosion as well as from general corrosion (see figure 1). The table below (figure 1) shows how the Critical Crevice Temperature and the Critical Pitting Temperature of some Hastelloys® and types of Stainless Steel. Hastelloy® C-22 alloy has a Critical Pitting Temperature greater than 140˚C whereas stainless steel type 316L only has a Critical Pitting Temperature of 15˚C. This shows that C-22 is a far better at resisting corrosion at higher temperatures than its Stainless Steel counterparts. The same applies to C-276; which is due to them containing a higher composition of carbon and molybdenum than that of Stainless Steel, Mild Steel and Iron.
A specific advantage of C-22 is that it can be easily welded. C-22HS has the same resistance as C-22 but it has double the yield strength.
Alloy Critical Crevice Temperature
˚C Critical Pitting Temperature
˚C
Hybrid-BC1 125 >140
C-4 50 100
C-22 80 >140
C-276 55 >140
C-2000 80 >140
316L 0 15
254SMO 30 60
625 40 100
Figure 1- Table ...
... middle of paper ...
...ure 2- Table showing Hastelloys® against Stainless Steel in terms of Cracking
A large number of Hastelloys® have low carbon contents, which reduces the carbide precipitation during welding. This also makes Hastelloys® more preferential over stainless steel. Hastelloys® which have a high composition of chromium are used in strong oxidizing mediums. For a range of physical properties of corrosion resistant Hastelloy see figure 4.
Works Cited
1. Haynes International, Available at: http://www.haynesintl.com/
(Accessed: 24th February 2014). – most information came from their Company website.
2. CSI Alloys, Available at: http://www.csialloys.com/about_advantages.php
(Accessed: 21st February 2014). - C-22 -> About C-22 -> Advantages
Figure 1
3. Megamex, Available at: http://www.megamex.com/hastelloy.htm
(Accessed: 20th February 2014).Hastelloy® -> Hastelloy® C-276
Raelians Raelians also love hierarchy. They group themselves into six levels, ranging from novice to Rael himself, who alone occupies the 6th level. Cocolios is a 3rd-level Raelian and a "regional guide." Chabot, a 4th-level Raelian and a "national guide," sets up an interview with Lear, a 5th-level Raelian. Adherence to the movement and to another religion * Adherence to the Raelian religion excludes adherence to another religion.
War is often followed by change; World War I is no exception. World War I is often labeled the cause for the rise of a feminine revolution-“the flapper”. Before the term “flapper” began to describe the “young independently-minded woman of the early Twenties” (Mowry 173), the definition that is most prominent today, it had a 300-year long history. The young woman of the 1920’s was new and rebellious. In her appearance and demeanor, she broke the social constructs of her society.
A wide variety of coating alloys and wrought alloys can be prepared that give the metal greater strength, castability, or resistance to corrosion or high temperatures. Some new alloys can be used as armor plate for tanks, personnel carriers, and other military vehicles.
These include, high strength, low weight, high chemical resistance and high cut resistance. This material does not corrode or rust and is also unaffected when placed in or under water.
“Satire is the use of humor, irony, or exaggeration to expose and criticize people's stupidity”. In the article from a mock press release, "The Onion", represents a new product called “MagnaSoles” which is described as the cheapest way out and is devoted to satirize the audience in order to emphasize techniques that companies use to get a hold of their consumers. The satire the Onion article uses illustrates how people are unable to properly judge their own flaws causing them to be gullible and easily deceived to what is in front of their eyes, evidenced by the pseudoscience the article mentions and the deceptive consumer testimonials.
When one thinks of flappers, the first thing that comes to mind is the image of a woman dressed much like Julie Andrews in Thoroughly Modern Millie, bobbed hair, fringed low-waisted dress, flat-chested and highly made up face. This, though a stereotype is close to the truth. In the 20’s after the first world war women’s roles in society began to change, primarily because they started becoming more independent – both in their dress and action. They started to defy what was considered to be appropriate feminine behavior and along with those actions came new fashions. The sleek, boyish look became popular and women began to wear lower waistlines, higher hemlines, sleeveless dresses that showed off their arms, long strands of pearls and rolled down pantyhose to show their knees. Women who had larger breasts even went so far as to bind them down to fit into the flat-chested ideal of beauty. The “in” look now was boyish, much in contrast to the feminine big skirted, shirtwaisted dresses of their mothers’ age. Women began to gain the independence and social liberties that men had always possessed, they wanted to physically display their newly gained freedoms. Short hair, first as a bob, later as a slicked down “shingle” that curled above the ears emphasized the new androgynous look women were trying to obtain. These “modern” women asserted their independence by going out dancing, moving to the city alone, drinking even during prohibition, flirting and having love affairs.
Aluminum is the second most abundant element in the Earth’s crust. It has a concentration of about 8.2 percent (Craig et al 264). Aluminum “is malleable, ductile, and easily machined and cast; and has excellent corrosion resistance and durability” (http://minerals.usgs.gov/). It is evident in everyday life.
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"Pulsed MIG Welding Improves Quality and Saves Money | Lincoln Electric." Lincolnelectric. N.p., n.d. Web. 27 Apr. 2014.
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