Flexural strength superior

Properties of Dense Silicon Carbide. Properties of the SiC stmctural ceramics are shown in Table 1. These properties are for representative materials. Variations can exist within a given form depending on the manufacturer. Figure 2 shows the flexure strength of the SiC as a function of temperature. Sintered or sinter/HIP SiC is the preferred material for appHcations at temperatures over 1400°C and the Hquid-phase densified materials show best performance at low temperatures. The reaction-bonded form is utilized primarily for its ease of manufacture and not for superior mechanical properties. 

Carbon-Fiber Composites. Cured laminates of phenoHc resins and carbon-fiber reinforcement provide superior flammabiHty resistance and thermal resistance compared to unsaturated polyester and epoxy. Table 15 shows the dependence of flexural strength and modulus on phenoHc—carbon-fiber composites at 30—40% phenoHc resin (91). These composites also exhibit long-term elevated temperature stabiHty up to 230°C. 

Amorphous polyarylates are light-amber transparent materials which exhibit mechanical properties comparable to that of unfilled PET in terms of tensile or flexural strength and modulus (Table 2.13) but are notably superior in terms of heat resistance (HDT = 174°C vs. 85°C for PET) and impact strength. 

Nylon-6-clay nanocomposites were also prepared by melt intercalation process [49]. Mechanical and thermal testing revealed that the properties of Nylon-6-clay nanocomposites are superior to Nylon. The tensile strength, flexural strength, and notched Izod impact strength are similar for both melt intercalation and in sim polymerization methods. However, the heat distortion temperature is low (112°C) for melt intercalated Nylon-6-nanocomposite, compared to 152°C for nanocomposite prepared via in situ polymerization [33]. 

The presence of the cement hydrate/polymer comatrix in LMM and LMC confers superior properties, such as high tensile and flexural strengths, excellent adhesion, high waterproofhess, high abrasion resistance and good chemical resistance, when compared to ordinary cement mortar and concrete. The degree of these improvements however depends on polymer type, polymer-cement ratio, water-cement ratio, air content and curing conditions. Some of the properties affected by these factors are discussed below [87, 88, 93-95]. 

The molded boards referred to above show excellent properties in HDT, tensile and compressive strengths, which are superior to those of the other series. The molded boards of the wood-MA-AGE series [83] exhibit HDT values of above 165°C and compressive strength of 160-230 MPa. The molded boards of the wood-PA-GMA series [84] exhibit outstanding properties in tensile strength (—69 MPa), flexural strength (—88-100 MPa), and Rockwell hardness (—120). 

In Fig. 4 and Fig. 5, flexural modulus and flexural strength of the cured resin depending on the adipic acid content are shown. It is found that flexural modulus of the cured resin decreased as the adipic acid content in the resin was increased. Introduction of adipic acid instead of maleic anhydride implies decrease of unsaturation of the resin. It seems that the decrease of flexural modulus resulted from decreased crosslink density due to lower unsaturation. It is of interest to note that flexural strength, on the contrary, tends to increase as the adipic acid content is increased. It is speculated that the cured resins of higher adipic acid content have more flexible chain and the flexural modulus are low compared with that of the cured resin of lower adipic acid content relatively. But, ultimate strength of the cured resin of higher adipic acid content is superior to the cured resin of lower adipic acid content due to possibly higher ultimate strain. 

Autoclave-cured specimens including FRP powder do not show superiority in flexural strength while water-cured specimens including 9.1% of FRP powder indicate excellent strength. 

In Fig. 3, flexural strength of the cement mortar into which ash were incorporated with and without polymer latex are shown. It is observed that flexural strength of the cement mortar decreased as the ash content were increased whether polymer latex was added or not. However, the flexural strength of the cement mortar with polymer latex was superior to that of cement mortar without polymer latex. Furthermore, the decrease of the flexural strength of the cement mortar with polymer latex was less than that of the cement mortar without polymer latex as the ash content was increased. 

The sulfur method has much greater flexural strength, racking strength, and tensile or bond strength. Impact and durability tests also indicate superior performance. 

VE polyurethane resins have mechanical properties similar or superior to those of conventional VE and epoxies. Characteristics include a heat distortion temperature of 120C (248F). Ultimate elongation of an unreinforced molding compound without fillers is 5.5% tensile strength is 80 MPa and flexural strength 150 MPa. The resins can be custom-formulated. Applications include customized automobile parts, recreational vehicles, outdoor equipment, tubs/showers and electrical parts. The resins are suitable for standard molding processes some were specifically developed for pultrusion, RIM, foam, adhesive, and polymer concrete applications. 

PEI is useful in applications where high heat and flame resistance low NBS smoke evolution, high tensile and flexural strength, stable electrical properties, over a wide range of temperatures, and frequencies, chemical resistance, and superior finishing characteristics are required. One such application is under the hood of automobiles for connecters and MAP sensors. 

Another recently launched material of the glass-ionomer type also contains novel components, in particular a patented diurethane monomer capable of polymerizing to give a set material of superior flexural strength and reduced brittleness. It is described as resin-modified glass-ionomer with the added description of bioactive ionic resin-based composite . 

Since the completion of the first edition of Fiber Chemistry, remarkable progress has taken place in the industrial applications of vinylon. The health hazards of asbestos, which had been used as reinforcement materials in cement, led to the search for an alternative cement-reinforcement fiber. Among the many fibers tested, vinylon showed the most superior performance. Figure 4.34 shows the flexural strengths of the slate in the presence... 

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