Melt Flow Rate ASTM D1238, ISO 1133

Melt Flow Rate ASTM D1238, ISO 1133

Melt Flow Rate (MFR) is a measure of ease of flow of melted plastics and is evaluated as Melt Flow Index or Melt Flow Rate by ASTM D1238, ISO 1133. MFR is used for differentiating grades of polyethylene or determining the extent of plastic deterioration caused by molding.


    Melt Flow Rate (MFR) is measured by ASTM D1238 and is helpful in estimating the extruder rate (using an extrusion plastometer) of thermoplastic resins through an orifice at a specified temperature and load. Melt flow rate indicates the ease with which melted plastics can flow. Due to the reduced molecular weight, the degraded materials will normally flow more, and might have diminished physical characteristics as well. So, it can be used for differentiating grades of polyethylene or determine the extent of plastic deterioration caused by molding. The flow rates of a component and the resin on which it is molded are evaluated and finally the percentage difference is calculated. 

    Test Procedure:

    ASTM D1238 uses an extrusion plastometer that consists of an extrusion barrel heated exactly to a specified temperature. A die of standardized diameter, and a piston with weight are applied to its upper end. The barrel of extrusion should be loaded into the barrel of the melt flow apparatus with the test sample which is approximately 7 grams. The material is placed on a plunger with a fixed weight and the molten material is forced through the die. The extrudate is collected at uniform time intervals and the weight is measured. The melt flow rate data are evaluated from the extruded mass (g) per 10 minutes.

    Specimen size:

    About 14 grams of material is required. 


    Flow rate = 600t*weight of extrudate


     t = time of extrudate in seconds and melt flow rate = grams per 10 minutes.


    Core Materials Testing Services


    A variety of microscopy and spectroscopy tools available for precise measurements from the nano to the meter scale.

    Metrology Testing Services


    TEM SIMS Profilometry

    Materials Testing

    ASTM and ISO standard and custom chemical, mechanical, thermal, corrosion tests, etc. for all materials metals, ceramic or polymers.

    Materials Testing Services


    Nondestructive Testing Electrical Testing Chemistry Analysis

    Product Testing

    Thousands of tests for product quality and reliability under heat, humidity, temperature shock, vibration, drop, electrostatic discharge.

    Product Testing Services


    Vibration Testing Humidity Testing Accelerated Aging

    Looking for Material Testing?

    We have 500+ Material Test already Done for top companies

      Send us a request