Although greatly outgunned, the crew of Stephen Hopkins fought back, replacing the Armed Guard crew of the ship's single 4-inch (100mm) gun with volunteers as they fell. These were simple but fairly large (for the time) with a single 2,500 horsepower (1,900kW) compound steam engine of obsolete but reliable design. In spite of (assured) very careful accident investigations no cause could be determined at that time [XIII-9]. Liberty ships were cargo ships built in the United States during World War II. Not named after people were: SSStage Door Canteen, named after the USO club in New York; and SSU.S.O., named after the United Service Organizations (USO).[16]. Brittle behavior of usually ductile materials is probably more commonly experienced under the following circumstances: Loaded with high strain rates under tensile stress with significant stress concentration often coinciding with multiaxial stress mode. Copyright 2023 Elsevier B.V. or its licensors or contributors. Installing crack-arresting devices such as riveted straps and strong weld seams to stop propagating cracks. Since the Schenectady and Esso Manhattan failures occurred in port, the ships could be put in drydock, repaired, and put back into service (Tassava 2003, pp. Eighteen American shipyards built 2,710 Liberty ships between 1941 and 1945 (an average of three ships every two days),[6] easily the largest number of ships ever produced to a single design. Therefore, a propagating crack in a brittle material cannot be stopped, and will proceed through the entire member of the structure. If the maximum stress exceeds the yield strength of ductile materials, plastic deformation reduces the sharpness of the crack tip towards a blunt, rounded tip. [34] The following year from 22 to 30 January 1944, Lawton B. Evans was involved in the Battle of Anzio in Italy. The number was doubled in 1939 and again in 1940 to 200 ships a year. Parts manufactured by one company were interchangeable with those made by another, and the openness of its design made most of its moving parts easy to see, access, and oil. The critical value for fracture is fracture toughness. It was one of the largest non-nuclear explosions in US history. [48], In 1953, the Commodity Credit Corporation (CCC), began storing surplus grain in Liberty ships located in the Hudson River, James River, Olympia, and Astoria National Defense Reserve Fleet's. Jumbo Liberty ship, in the 1950s some Liberty ships were lengthened in Japan. Hatch corner in a supply ship, inadequate (a) and improved (b) design variants. Although BCC and FCC crystals have the same amount of slip systems, the activation energy for these slip systems is higher in BCC metals due to the longer distance between two energy minima [, For these reasons, slow strain rates tests such as tension or torsion tests at room temperature alone are not sufficient to investigate the mechanical properties of materials. Values of Kch which are relevant to real conditions lie close to 2.0. The predecessor designs, which included the "Northeast Coast, Open Shelter Deck Steamer", were based on a simple ship originally produced in Sunderland by J.L. Editors select a small number of articles recently published in the journal that they believe will be particularly But the Schenectady fracture was the first to happen in full view of the population of a major city, and hence the first to attract widespread attention. 2016 by the author; licensee MDPI, Basel, Switzerland. [64] SS Benjamin Chew had its existing condensers modified and a new superheater and geared turbine installed to give the ship 6,000 shp, up from 2,500. [4] The increase in production of more suitable vessels did allow for returning the hastily converted Liberty ships to cargo-only operations by May 1944. Figure 1.13. River patterns are also common on the cleaved surfaces. When it came to IT consulting services, Adamas Solutions proved to be a real expert. https://doi.org/10.3390/challe7020020, Subscribe to receive issue release notifications and newsletters from MDPI journals, You can make submissions to other journals. [67] Three were scrapped in 1971 or 1972 and the diesel-equipped Thomas Nelson was scrapped in 1981. This means that the material will suffer a catastrophic fracture, before it would yield [. Increase revenue by saving your money and focusing your core team on the main project. This results in an increase of the crack size and a consequent increase of the stress concentration factor. The problem is substantially slowing the cruise ship. WebWhile not glamorous, the Liberty Ship proved vital to the Allied war effort. [15], Any group that raised war bonds worth $2million could propose a name. [68], Liberty ships were built at eighteen shipyards located along the U.S. Atlantic, Pacific and Gulf coasts:[69]. More than 2,400 Liberty ships survived the war. WebThe failure of many of the World War II Liberty ships is a well-known and dramatic example of the brittle fracture of steel that was thought to be ductile. The fight was short, and both ships were wrecks. This article is about the class of US cargo ship. You seem to have javascript disabled. 120 subjected to varying load cases dependent on the dimension ratios r/h and b/h.94 With r/h0.2, the factor Ks01.4 was produced for existing ship designs. These were made of either 3% or 5% nickel alloy steel and impact tests showed that their notch-ductility was very low indeed. In contrast, bend testing (Fig. Change), You are commenting using your Twitter account. Welding is one of the most versatile of joining processes. Ship types included two tankers and three types of merchant vessel, all to be powered by steam turbines. Nineteen ships broke in half without warning. 6.15, left) and related these to the crystallinity that she had observed on the crack surfaces (Fig. 6.15 shows the primary metallurgical contribution that Tipper made by observing the fracture surfaces from the cracked ships under a microscope. Image: Mothball Fleet of WWII Liberty Ships in Hudson River off Jones Point 1957, Merchant Marine Distinguished Service Medal, critical ductile-brittle transition temperature, Allied technological cooperation during World War II, Center of Military History, United States Army, "Liberty Ships built by the United States Maritime Commission in World War II", "African-Americans in the U.S. 11.12 (right), the JKR test for cracking the contact between two spheres. In contrast to ductile failures, brittle fracture usually occurs without any noticeable deformation. Another notable Liberty ship was SSStephen Hopkins, which sank the German commerce raider Stier in a ship-to-ship gun battle in 1942 and became the first American ship to sink a German surface combatant. Problems arise when some unexpected mode of deterioration or failure occurs, like the lamellar tearing that led to the loss of the Alexander L Kielland platform. The new design replaced much riveting, which accounted for one-third of the labor costs, with welding. Liberty Ship Failure Case Study | Best Writing Service Finished Papers REVIEWS HIRE Write an essay from varied domains with us! WebGeneralities: catastrophes due to brittle failure The two cases of catastrophic brittle failure described share two common features with the Liberty ships: the steel had a low notch In order to be human-readable, please install an RSS reader. The predominantly welded (as opposed to riveted) hull construction then allowed cracks to run large distances unimpeded. Also, there are no temperature and crack speed data, the missing links in the Liberty ship disasters. Several weeks later, it snapped in half at the keel and the two pieces sank. The welds produced by largely unskilled work force contain crack type flaws. Blame tended to point at the shipyards, which built the Liberty ships very quickly (the record was launch 5 days after laying the keel) with inexperienced, often female, workers, and uncalibrated welding techniques (Fig. [28], In September 1943 strategic plans and shortage of more suitable hulls required that Liberty ships be pressed into emergency use as troop transports with about 225 eventually converted for this purpose. In Portland, Oregon, the hulls of Richard Henry Dana and Jane Addams serve as the basis of floating docks. It could be argued that the problem is not that of providing a temporary safe haven, which is a straightforward design job, but how to persuade all the crew, not just the bold ones, to face the hazards and discomforts of the open sea. Under certain circumstances, materials that generally show ductile behavior can lose their fracture toughness and become brittle, likely resulting in catastrophic failure. By the Second World War the development of electric power sources and welding electrodes had made welding a commercial industrial process. Again, air and water temperatures were cold; however, the ship was unloaded and in calm water. The initial design was modified by the U.S. Maritime Commission to conform to American construction practices and to make it even quicker and cheaper to build. In other words, some of the ships plates were very tough in freezing sea water, whereas some others of the same specification were hopelessly brittle. Furthermore, mobile non-destructive radiography equipment to monitor weld quality was not available at that time, so quality control as we know it today was not possible 60 years ago. In case of significant segregations on the grain boundaries, the crack can also propagate in an intergranular way [. No attention was paid to how welding would affect the structure. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Click to share on LinkedIn (Opens in new window), Click to share on Facebook (Opens in new window), Click to share on Twitter (Opens in new window), Click to share on Reddit (Opens in new window), Click to share on Tumblr (Opens in new window), Click to share on Pinterest (Opens in new window), Click to share on Pocket (Opens in new window), Click to email a link to a friend (Opens in new window), Water (Its Volume Expansion UponFreezing). Tipper had measured the energies from the Charpy impact tests (Fig. Tassava is a historian, not an engineer, but does a good job of reviewing the technical issues associated with the failures. She relates how the Liberty Ship crisis was a new phenomenon in 1943, many ships cracking in quick succession, while only one previous steel structure had failed as a result of cracks influenced by notches and low temperatures, the Hasselt Bridge in Belgium in 1938. 119. Merchant Marine and U.S. Maritime Service during World War II", "Report on the Wreck of the SS Richard Montgomery", "The Hoverfly in CBI, Carl Warren Weidenburner", X-FEM for Crack Propagation Introduction, "Asbestos and Ship-Building: Fatal Consequences", Case Details - Brittle fracture of Liberty Ships, "Lawton B. Evans (American Steam merchant) Ships hit by German U-boats during WWII", "Papahnaumokukea Expedition 2007: Liberty Ship SS Quartette", "Papahnaumokukea Marine National Monument: Liberty Ship SS Quartette", "Papahanaumokuakea Marine National Monument: Pearl and Hermes Atoll", "Hudson River National Defense Reserve Fleet", "Operation "Pluto" Arthur M. Huddell, James River Reserve Fleet, Newport News, VA", "Did You Know: Liberty Ships Still Afloat in Portland", "Floating Nuclear Plant Sturgis Dismantled", "Proceedings of the Merchant Marine Council", "Postal Service Salutes U.S. All these ideas were known and proved in the 1970s when the proper analysis was carried out at Akron University. However, considering the constraints of that time, considering the fact that large cargo ships were needed quickly, sufficient steel not being available and qualified labor being short, there are not many improvements that could have been suggested at that time. In Assessment of Safety and Risk with a Microscopic Model of Detonation, 2003. The trend to a 1 in 10 failure rate at short crack lengths for ( T - T 27 J) of 20 C is consistent with the Liberty ship casualty statistics. In the 1960s, three Liberty ships and two Victory ships were reactivated and converted to technical research ships with the hull classification symbol AGTR (auxiliary, technical research) and used to gather electronic intelligence and for radar picket duties by the United States Navy. Webthe material failures and design flaws that contributed to the rapid sinking of the Titanic. Weyerhaeuser operated a fleet of six Liberty Ships (which were later extensively refurbished and modernized) carrying lumber, newsprint, and general cargo for years after the end of the war. As America entered the war, the shipbuilding yards employed women, to replace men who were enlisting in the armed forces. The modifications into troop transports also were not given special type designations. The U.S. Liberty Ship Building Program in World War II set a recorda total of 2700 Liberty Ships were built in 6 years, in order to support the battle against Nazi-Germany. The first Ocean-class ship, SS Ocean Vanguard, was launched on 16 August 1941. [citation needed], The Ministry of War Transport borrowed the British-built Empire Duke for testing purposes. permission is required to reuse all or part of the article published by MDPI, including figures and tables. It was discovered that the ships in the North Atlantic were exposed to low temperatures that changed the mechanism of cracking from ductile to brittle, causing the hull to fracture easily. Challenges 2016, 7, 20. most exciting work published in the various research areas of the journal. The mechanism by which transgranular fracture occurs is cleavage, a process that occurs preferentially along specific crystallographic planes. Obviously, the relationship of stress and strain was already known in the 1940s, and the designers should have known that rectangular corners need to be avoided. Ships in the North Atlantic were exposed to temperatures that could fall below this critical point. President Franklin D. Roosevelt praised the welding that made the Liberty Ships possible in a letter to Britains Prime Minister Winston Churchill. It soon became clear that the lab tests may not have been representative of the true operational conditions of the ships, when the amazing woman scientist Constance Tipper (Fig. Their production mirrored (albeit on a much larger scale) the manufacture of "Hog Islander" and similar standardized ship types during World War I. But then many engineers recognize that bending strength is higher than tensile strength of the same samples, as explained by the fracture energy analysis of Chapter 5.7. Between 1955 and 1959, 16 former Liberty ships were repurchased by the United States Navy and converted to the Guardian-class radar picket ships for the Atlantic and Pacific Barrier. WebThe failure of many of the World War II Liberty ships is a well-known and dramatic example of the brittle fracture of steel that was thought to be ductile. WebIn fact ten USMC ships, eight of them standard Libertys, had already suffered a serious fracture by the time of the Schenectady incident. Visit our dedicated information section to learn more about MDPI. Hydrogen is apparently drawn to incipient or preexistent grain boundary cracks, stabilizing them against the tendency of the surrounding metal to blunt their advance. Welding is significantly faster than riveting, as borne out by the production of a welded Liberty ship in a matter of days at its fastest, rather than weeks or months when riveting. Improving welding practices and establishing welding codes. Such experiences suggest that some structures can be very tolerant of embrittlement. To discuss the reasons for these failures, the representative fates of two different ships will be discussed. During World War II there were nearly 1,500 instances of significant brittle fractures. Disclaimer/Publishers Note: The statements, opinions and data contained in all publications are solely positive feedback from the reviewers. Similar was the case with NASAs shuttle booster joint. In the early Class I failures, such as the Schenectady and Esso Manhattan, the cracks had been able to travel completely through the hull. In 2000 new facts appeared in a Hollywood movie based on history and also in the Internet [XIII-9a], [XIII-9b], which annihilate the cause investigations of the Army-Navy Explosives Safety Board. 10-28 demonstrate. [4] The reader may note that corners of windows and doors for all of todays marine and aircraft structures are rounded. Source:Materials Science and Engineering An Introduction 9th Edition [Callister & Rethwisch]. The complete case study is provided in Chapter 9 of Beyond Failure: Forensic Case Studies for Civil Engineers. Two years after the war an official board of investigation determined that faulty workmanship caused exactly 25 % of the 2,504 fractures which had occurred up to August 1, 1945, that a combination of inferior workmanship and inadequate design caused another 20 %, and design so poor that perfect workmanship would have done little to prevent the failures caused a stunning 55 % (Tassava 2003, p. 103). Solid-state welds have been made for centuries; working two red-hot iron pieces in the forge by striking with a hammer until a joint is made. [40] In August 1945, William J. Palmer was carrying horses from New York to Trieste when she rolled over and sank 15 minutes after hitting a mine a few miles from destination. Some of the early In other words, the steel had been grossly misused in one way or another. In 2011, the United States Postal Service issued a postage stamp featuring the Liberty ship as part of a set on the U.S. Twenty Class I failures occurred in January 1944, The solutions fell into three categories improvements to shipyard practice, retrofits of the completed ships, and changes to the design. Skilled game designers, game artists, and developers will implement any of your game ideas. It is important to note that the effect of stress raisers is much more significant in brittle than in ductile materials. She was named after the chief engineer of a United States Army freighter who had stayed below decks to shut down his engines after a 13 April 1945 explosion, an act that won him a posthumous Merchant Marine Distinguished Service Medal. The notch effect can be reduced by design measures (gusset plate with rounded profile or rivets instead of welding).98. Three of them catastrophically split in half when cracks formed, grew to critical lengths, and then rapidly propagated completely around the ships girths. Cracks propagate rapidly. We need to acknowledge the fact that the emergency Liberty Ship building program was a project that has not been seen before and after. High toughness region: Main failure mode is the ductile fracture (shear fracture). Although this fleet was used for war purposes only, it was never part of the U.S. Navy. In March, another tanker, the Esso Manhattan, split in half while entering New York harbor. MDPI and/or The right-hand curve in Fig. Our team has years of experience in developing, testing and maintaining software products. In such cases the crack propagates across and through the grain interiors. A welded alternative is to simply butt two plates together and perform a full penetration weld. Fig. That was the reason why Liberty ship hatches and Comet windows were modified to prevent cracks starting at the sharp square corners. William Patterson was considered to be a failure as reliability was poor and the scalability of the design was poor. In 1940 the British government ordered 60 Ocean-class freighters from American yards to replace war losses and boost the merchant fleet. Such failures (Fig. At its peak in 1965, 189 hulls were stored there. But the energy for breakage is much greater for the riveted joint. The second was to install crack-arresting devices, to stop cracks from propagating through the hulls. Dieter Radaj Dr-Ing habil, in Design and Analysis of Fatigue Resistant Welded Structures, 1990. The article concludes with a review of the causes and effects of the rapid sinking of the Titanic. Milton Ohring, in Engineering Materials Science, 1995. This paper demonstrates and investigation of the Liberty Ships failure and problems, which reveals that the failures are caused by a combination of three factors. The subsequent history of these vessels is not known, but they had operated perfectly satisfactorily up to the time of the explosion. During the investigation that followed a vapour cloud explosion at an ethylene plant, samples were taken from two of the distillation towers that operated at subzero temperature. Early Liberty ships suffered hull and deck cracks. Under these conditions, the yield point is likely raised above the ultimate tensile strength of the material. 10-29B) reveal clearly outlined grains that appear to be deeply etched or stand out in relief like rock candy. The ultimate tensile strength of the U.S. Navy hull construction then allowed cracks to run large distances unimpeded measured energies... 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Varied domains with US good job of reviewing the technical issues associated the! The Allied war effort hull construction then allowed cracks to run large distances unimpeded close to 2.0 associated. Of significant segregations on the cleaved surfaces case Study is provided in Chapter 9 Beyond... Metallurgical contribution that Tipper made by observing the fracture surfaces from the cracked ships under a microscope artists and... Cracks starting at the sharp square corners: //doi.org/10.3390/challe7020020, Subscribe to receive issue release notifications and newsletters MDPI.