Bulletproof Vests-Kevlar MCV @introtomaterialsscience--g4

Uploaded April 2015 | Updated September 2026, 3 hours ago

Bulletproof Vests: Engineered to Protect

For our materials science challenge video, we wish to discuss Kevlar: the main material used in bulletproof vests. Whether an individual is at war in a foreign country, a member of the police force, FBI or CIA, or even a recreational hunter, a certain and expected amount of protection from projectiles around them may be necessary. A material needs to be relied on to ensure the safety of the individual in an effective as well as efficient way. Since the invention of the gun, many different types of bulletproof vests have been constructed, all out of a vast array of materials. While initially fashioned of metal and thick cloth, materials science has played a significant role in the evolution of the vest and saving lives as new materials have been processed. Materials such as Kevlar have revolutionized the protection of those in harm’s way. In our video, we wish to explore the history of the bulletproof vest while comparing different materials that have been used over the ages. We also hope to explore the compositions and structure of Kevlar to better understand how it has been utilized and designed with protection in mind. We will also investigate one of the most significant challenges that can be associated with bulletproof vests that is found in trading weight for strength, along with some of the methods used to combat this delicate balance. Finally, we desire to examine how Kevlar performs in action and the properties that it exhibits when met with a speeding projectile. In doing so we not only hope to better understand Kevlar on a material basis, but also the magnitude of some of the situations that others are placed into for the protection of the greater good.
Sources:
Ashdown, Charles H. Arms & Armour. New York: Dodge, 1909. Print.
BodyArmorNews.Com. "How Does Armor Work?" Body Armor News. N.p., 2014. Web. 14 Apr. 2015. bodyarmornews.com/bullet-proof-vest/.
DuPont. Kevlar: Aramid Fiber. Dec. 1992. Technical Guide. U.S.A. Print.
Howell, Elizabeth. "Future Soldiers May Wear Bulletproof Spider Silk." LiveScience. TechMedia Network, 25 June 2014. Web. 20 Apr. 2015. livescience.com/46519-spider-silk-bulletproof-clothing.html.
Lacombe, Paul M. Arms and Armour in Antiquity and the Middle Ages. New York: D. Appleton, 1870. Print.
Woodford, Chris. “Kevlar.” ExplainThatStuff. N.p., 2008. Web. 20 Apr. 2015. explainthatstuff.com/kevlar.html.
Yang, H. H. Kevlar: Aramid Fiber. Chichester: J. Wiley, 1993. Print.

Additional Images and Animations:

youtube.com/watch?v=WETkwH6eI5M

wolfcomusa.com/images/vest-police-cam.JPG

toptenz.net/wp-content/uploads/2013/04/battle-of-plataea.jpg

imgsrv.legends1027.com/image/wlgz/UserFiles/Image/Wiki%20Corner/Stephanie-kwolek.jpg

usmilitarybodyarmor.weebly.com/uploads/1/0/5/2/10524902/8708218_orig.jpg

easycomposites.co.uk/images/products/large/kevlar-flat-braid-45mm.jpg

cdn.modernfarmer.com/wp-content/uploads/2014/11/Silk-thread_Lucas-Barthforweb.jpg

youtube.com/watch?v=EJln-sCpU98

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upload.wikimedia.org/wikipedia/commons/7/70/Testing_bulletproof_vest_1923.jpg

factsden.com/wp-content/uploads/2010/10/darwin-bark-spider.jpg

k9s4cops.org/wp-content/uploads/2014/06/inside_photo.jpg

assets.inhabitat.com/wp-content/blogs.dir/1/files/2010/11/Organic-Bullet-Proof-Vest-1.jpg

t1.gstatic.com/images?q=tbn:ANd9GcQIerXlsGgH4DakyphXvVnkz162yB3U5pgrkdwD2NpcOOVEx2NpXTXHw

upload.wikimedia.org/wikipedia/commons/9/91/FileArmy_IOTV.jpg

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$Titanium Implants- Nickel MCV Materials Challenge: Implants I am Titanium For centuries, humans have been searching for materials to replace damaged or failed human tissue. These tissue replacements, or implants, have included everything from bits of shell hammered into the jaw to replace missing teeth to the metal hip and knee replacements we see today. There are many unique challenges in selecting materials for implants, as in addition to having properties similar to the failed biological component the implant must repair or replace, any material used must not be toxic to the human body. Titanium is a commonly used material in implants because it is strong, durable, and bonds with bone. It is not perfect, however, the high Youngs modulus, or stiffness, of titanium can result in stress shielding where the implant bears more of the bodys load than the surrounding bone, causing the bone tissue to weaken and fracture. Our video will provide an introduction to implants by defining the term, giving a brief history of the development of implants, and giving some examples of the types of implants used today. We will then discuss the specific properties required of implants, including strength, durability and biocompatibility. We will then discuss titanium implants specifically the properties of titanium, what makes it work well for implants, as well as some of the challenges associated with the use of titanium and its alloys. We will discuss stress shielding in more detail, and demonstrate cold working a process by which the yield strength of metals can be increased without affecting the Youngs modulus. References: 1. Arsenjev, A. P.; Arsenjev, P. A.; Evdokimov, A. A.; Makaricheva, E. U.; Sheinin, M. J., The processing of surgical implants from pure titanium, Biomedical Engineering Conference, 1996., Proceedings of the 1996 Fifteenth Southern , vol., no., pp.384,385, 29-31 Mar 1996 http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=493256&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D493256 2. C.N. Elias, J.H.C. Lima, R. Valiev, and M.A. Meyers. Biomedical Uses of Titanium and its Alloys. JOM, March 2008. Pgs 46-49. http://www.meyersgroup.ucsd.edu/papers/journals/meyers%20316.pdf 3. M. Niinomi and M. Nakai, Titanium-Based Biomaterials for Preventing Stress Shielding between Implant Devices and Bone, International Journal of Biomaterials, vol. 2011, Article ID 836587, 10 pages, 2011. http://www.hindawi.com/journals/ijbm/2011/836587/ 4. Neailey, K., and Pond, R.C. (1982). Metal implants. Materials & Design, Volume 3, Issue 3, Pages 470-478. http://www.sciencedirect.com/science/article/pii/0261306982901133. 5. Springer Science+Business Media. (2011, July 26). Heavy metal: Titanium implant safety under scrutiny. ScienceDaily. Retrieved May 5, 2014 from www.sciencedaily.com/releases/2011/07/110725101257.htm 6. Slides from a Materials Science/Biomaterials Course; details processes, properties and uses of metallic biomaterials: http://www.bioen.utah.edu/faculty/pat/Courses/biomaterials2006/Metals%20and%20Applications%20in%20Orthopedics.pdf 7. How Its Made (YouTube clip): Titanium Dental Implants https://www.youtube.com/watch?v=S4j_GOYFoG8 All unoriginal images were unlicensed and accessed through Wikipedia. Titanium by David Guetta ft. Sia$