What is Rebar?
Rebar is a steel bar, which is used to reinforce and strengthen concrete under tension. It is made up of reinforced hardened concrete, which is made up by a list of composite material. The accurate information on the properties of the rebar steels is important at the construction stage.
What make up the composite material in a steel rebar?
Steel rebar is very useful in all sectors of economy such as machine building and factory infrastructures. Therefore, quality testing should be directed to steel manufacturing industries so that they can meet up with the global challenges in the steel industry.
Steel is an alloy of iron and carbon containing up to 1.5% Carbon. Steel are made by oxidizing the impurities that are present in iron produced in the blast furnace
The percentage composition of carbon between 0.05-1.5 percent played a major role in steel classification/grading. The percentage of carbon in each steel class has a direct influence on its hardness.
Therefore the chemical analysis of a given sample of steel can determine the class of steel from which the sample is being taken through evaluation of its percentage carbon content.
Why do we need to conduct chemical Analysis Test for Rebar?
As mentioned, Rebar is used to strengthen concrete under tension. Therefore, it is really important to conduct chemical testing to validate the level of chemical contents in the rebar. In this way, key players are able to find out if there is any deviant chemical substance in the sample.
Chemical composition variations in producing reinforcing steel bars are unavoidable, thus it is important to allow the rebar to go through chemical analysis test. It is done to inspect the level of chemical composite used in the rebar, which is used for construction purposes. In this way, the rebar will be safe to use for construction of building.
Spark Optical Emission Spectrometry OES (Spark-OES)
With our in house laboratory, PTS testing team will apply the rebar sample on our Spark-OES analysis machine.
As the spinning abrasive wheel is applied to the sample, the sparks that are emitted are compared to a chart. The appearance of the sparks indicates the elemental chemical composition of the metallic surface.
The analysis of the steel rebar would need to show that it is indeed high in carbon steel, and verify amounts of other elements, such as silicon, manganese, phosphorus, and sulfur. Spark-OES analysis can detect these elements at very low levels.
Inductively Coupled Plasma Optical Emission Spectroscopy (ICP – OES)
ICP-OES is a fast elemental analysis method, which is capable of testing large sample batches in a short period of time. With ICP-OES, PTS can detect trace elements at trace levels in your rebar sample.
ICP-OES can provide expanded element coverage and sensitivity ranges. PTS testing team will ensure that your sample is dissolved completely into aqueous solution before analysis. The dissolved sample is aspirated into the plasma and ionized. Ions from the plasma are input to a mass spectrometer. This method will determines which elements are present in the plasma.
Combustion Method for Carbon & Sulfur
The accurate determination of these elements in rebar is important. PTS in-house laboratory has the facility to carry out combustion method for Carbon & Sulfur testing.
This method determines the sulfur and carbon concentrations in the range from mass percent levels down to trace parts-per-million. Thus, elemental analysis is capable of qualifying and certifying specific compositions in rebar.
The samples will be prepared in the form of chips and they will be melt by an extremely high temperatures by solid-state induction furnace. A high flow of oxygen will be apply, which will combust carbon and sulfur to carbon dioxide (CO2) and sulfur dioxide (SO₂). Both element are measured with electronic detectors like infrared cells, which defines SO₂ and CO2 concentration within the gas flow.
Inert Gas Fusion for O,N,H
Oxygen (O), nitrogen (N) and hydrogen (H) strongly influence the properties of metal such as steel, copper, refractory metals. One of the example is steel rebar. These elements play an important part of the quality control process for metal.
PTS testing team will apply inert gas fusion technique, which is based on hot extraction analysis. The metal sample will be heat in an impulse furnace, which will be melted in a graphite crucible. Inert gas fusion is use to determine the quantitative content of gases. The element O, N, H are physically and chemically adsorbed by the materials, which will be removed and swept by from the fusion area by an inert carrier gas.