SiC coating with high crack resistance property for carbon/carbon composites

Abstract The high mechanical properties of the Al-Li-X alloys contribute to their increasingly broad application in aeronautics, as an alternative for the aluminium alloys, which have been used so far. The aluminium-lithium alloys have a lower specific gravity, a higher nucleation and crack spread resistance, a higher Young’s module and they characterize in a high crack resistance at lower temperatures. The aim of the research planned in this work was to design an aluminium alloy with a content of lithium and other alloy elements. The research included the creation of a laboratorial melt, the microstructure analysis with the use of light microscopy, the application of X-ray methods to identify the phases existing in the alloy, and the microhardness test.

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Crack resistance of tool steels corresponding with the chemical composition of their matrices

Archives of Materials Science and Engineering ◽

10.5604/01.3001.0010.4868 ◽

2017 ◽

Vol 1 (86) ◽

pp. 5-14

Author(s):

J. Pacyna

Keyword(s):

Chemical Composition ◽

Crack Resistance ◽

Phase Transformations ◽

Charpy Impact ◽

Charpy Impact Test ◽

Tool Steels ◽

Industrial Practice ◽

High Crack ◽

Secondary Precipitates ◽

Kinetics Of

Purpose: of the presented investigations was showing that the crack resistance of tool steels depends on their hardenability and phase transformations occurring in the quenched matrix at tempering. The chemical composition of austenite decides on the steel hardenability while phase transformations after tempering can be influenced (apart from the chemical composition) by the heating method. Design/methodology/approach: of investigations was based on the analysis of dilatograms and the achieved aim was to obtain the hard tool steel (app. 500 HV30) for hot works. Samples of a diameter of 10 mm (without a notch) made of this steel were not broken by the Charpy impact test of energy of 30 kGm. Findings: of these investigations are practical. Grain boundaries of prior austenite should be protected against secondary precipitates, which constitute natural nuclei of diffusive structures. It is also possible to control phase transformations at tempering. Research limitations/implications: constitute the availability of the adequate equipment for investigating the kinetics of phase transformations of undercooled austenite and the kinetics of phase transformations after tempering. Practical implications: for the industry are such that the proposed tool steels of a high crack resistance contain molybdenum and nickel. Thus, these steels are very expensive. Originality/value: of these investigations was confirmed in the industrial practice.

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Experimental Study on Spray Materials at Low Temperature

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.466-467.93 ◽

2012 ◽

Vol 466-467 ◽

pp. 93-96

Author(s):

Yue Zhong Lin ◽

Yong Qiang Lai ◽

Li Jie Zheng

Keyword(s):

Experimental Study ◽

Low Temperature ◽

Experimental Research ◽

Economic Performance ◽

Polymer Fiber ◽

Spray Process ◽

Cement Retarder ◽

High Crack ◽

High Crack Resistance ◽

Early Strength

According to the low temperature spray process, using double quick cement, retarder, water retaining agent, water reducing agent, polymer, fiber was investigated using orthogonal theory the feasibility of preparation of guniting material. Through the experimental research prepared early strength, high adhesiveness, high crack resistance, high economic performance of gunite material, its each index can meet the requirements of the application.

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Experimental investigation on strength properties of concrete using polypropylene pellets

International Research Journal of Multidisciplinary Technovation ◽

10.34256/irjmtcon74 ◽

2019 ◽

pp. 517-519

Author(s):

Anand G ◽

Velumani M ◽

Sakthivel S

Keyword(s):

Acid Resistance ◽

Strength Properties ◽

Water Penetration ◽

Hardening Process ◽

Test Water ◽

High Crack ◽

Water Absorption Test ◽

High Crack Resistance ◽

Test Result ◽

Better Than

The handmade tiles are manufactured in Athangudi, Sivagangai district. We observed that these tiles are reducing foot pain and appearing aesthetic look. But one disadvantage was that these Athangudi tiles were getting easily cracked. We studied that these tiles are getting cracks. Due to its lesser resistance. It shows some cracks on surface of tiles after setting and hardening process. In this project, we gave solution to rectify the problem for this purpose we adding the zirconium di oxide to cement paste at the time of manufacturing process. Because the zirconium di oxide possess high crack resistance property in these tiles. The field test (water penetration test), abrasion test, water absorption test and acid resistance test were conducted on Athangudi tiles with zirconium di oxide and without zirconium di oxide. Then the test result was compared between normal tiles and zirconium di oxide used tiles. Hence we conclude that zirconium di oxide used tiles are somewhat better than normal Athangudi tiles from the above result. We will conduct more tests and come with the conclusion that zirconium di oxide used tiles having better cracking resistance in future.

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Study of Crack Resistance Property of Polyvinyl Alcohol Fiber Reinforced Concrete

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.287-290.178 ◽

2011 ◽

Vol 287-290 ◽

pp. 178-182 ◽

Cited By ~ 3

Author(s):

Kai Tao Xiao ◽

Jia Zheng Li ◽

Hua Quan Yang

Keyword(s):

Elastic Modulus ◽

Reinforced Concrete ◽

Polyvinyl Alcohol ◽

Crack Resistance ◽

Drying Shrinkage ◽

Fiber Reinforced Concrete ◽

Fiber Reinforced ◽

Polyvinyl Alcohol Fiber ◽

Resistance Property ◽

Pva Fiber

The strength, ultimate tensile value, compressive elastic modulus and drying shrinkage of polyvinyl alcohol fiber reinforced concrete were studied by tests, and its crack resistance property was also studied by plate method and temperature stress testing machine. The test results showed that PVA fiber could improve the tensile strength and ultimate tensile value of concrete, lower its compressive elastic modulus and drying shrinkage, restrain its early plastic shrinkage and drying shrinkage cracks, reduce its cracking temperature and improve the crack resistance property of concrete, moreover, the effect of long PVA fiber was better.

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