Cast iron analyzer
Cast iron is a general term for alloys mainly composed of iron, carbon and silicon. In these alloys, the carbon content exceeds the amount retained in the austenite solid solution at the eutectic temperature. An iron-carbon alloy containing more than 2% carbon. Industrial cast iron generally has a carbon content of 2.5% to 3.5%. Carbon is mostly in the form of graphite in cast iron, and sometimes in the form of cementite. In addition to carbon, cast iron also contains 1% to 3% of silicon, as well as manganese, phosphorus, sulfur and other elements. Alloy cast iron also contains elements such as nickel, chromium, molybdenum, aluminum, copper, boron, and vanadium. Carbon and silicon are the main elements that affect the microstructure and properties of cast iron.
In order to produce cast iron of different performances and types, it is necessary to use cast iron analyzer to detect and analyze the content of various elements in cast iron, and the analysis of carbon and sulfur content is especially important. Infrared method is widely used to measure carbon and sulfur. Accuracy and accuracy, the following describes the measurement of the underlying adsorption blank and blank value.
Surface adsorption blank: The CO 2 in the air is 394×10 -6 , accounting for 0.04%. The sample, the standard steel or the additive, especially the powder sample, have a large surface area and it is inevitable to adsorb CO 2 . In the analysis of ultra-low carbon, analysts often use ethanol to wash the mixture to remove the amount of carbon adsorbed, and then dry it for analysis. However, for surface carburization and carbonization caused by sampling, cleaning is not acceptable. For sheet-like samples, such as racket samples, the surface can be polished with alumina or sampled with a newly developed domestic thick sampler. Reduce surface carbonation.
Determination of blank value: The blank value is the sum of carbon and sulfur released by oxygen, flux, helium and combustion system. The determination method is direct method and indirect method.
The indirect measurement method, also known as the standard addition method, is to add a known amount of a standard sample and measure the carbon amount or the sulfur value under the analysis conditions. Blank value = measured value - standard value. The average value can be measured multiple times. The direct blank measurement method, without adding a sample, only adding an additive, and measuring the amount of carbon and sulfur under the condition of simulated analysis, is a blank value. The direct blank method is usually input at 1 g, however, when the sample is measured, the sample may not be 1 g, and the actual blank value is usually adjusted as follows:
Blank value = measurement blank × 1g / sample weight
In order to ensure the representativeness of the blank value, it is preferable to use the average value of the blank compensation more than three times, and it is necessary to pay attention to the consistency between the blank and the condition of the analysis sample. In particular, the added additives W, Sn and Fe are preferably metered in. Especially for the analysis of low carbon and low sulfur, the blank value affects the accuracy and accuracy, and the blank value is required to be low and stable.
Cast iron analyzer infrared carbon and sulfur analyzer surface adsorption blank and blank value determination for the time being introduced so much, I hope to improve the accuracy and accuracy of analysis when you analyze.
Kolon aramid yarn, Kolon Industries Inc,Indoor/Outdoor Optical Cable
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