Hello, I am looking for a more in-depth source other than the ASTM standards for pressure vessel material grades that have additional mechanical properties in terms of fracture toughness, elongation at break, ductile to brittle transition, etc. Does anyone know if the ASME books contain mechanical properties beyond the typical yield, ultimate strengths and elongation? Thanks in advance!

rjleslie ASTM standards or ASME code for pressure vessel grade materials to be used will specify general requirements from T.S/ mechanical properties like elongation , toughness, R.A with ref to temp Codes or standards will not give beyond this. If you would like to derive specific improvement in mechanical properties - viz., toughness, elongation etc you may have to specify specific heat treatment processes to be adopted or followed for the particular grade material chosen for your requirements. Codes / Standards will not give this. If you need specific improvement on NDT properties - which is a time- temp related performance of a particular grade material - which can transform from ductile to brittle transition - you have to again consider choosing a material with different heat treatment processes to improve NDT or choose specific alloying additions that will improve ductile to brittle transition temperature properties. For ex: When medium alloy steel materials were developed for moderately severe corrosion / temperature services in early 1930's only 5 Cr allloy addition was considered safe from improving corrosion/ oxidation and mechanical properties improvements. Later with service failures during long time exposure and transition from Room temp after cooling and again re heating to higher temp after long service exposures, a small alloy addition of 0.5 Molybdenum was done to improve the NDT properties of the same 5 Cr materials. A small addition of 0.5% Mo improved dramatically the NDT ( ductile to brittle transition for such grade materials in high temperature corrosive services). Hope this helps C.V.Srinivasan August 5, 2010 Nishi Engineers Pvt Ltd India E-mail: nishi@vsnl.com >Hello, > >I am looking for a more in-depth source other than the ASTM >standards for pressure vessel material grades that have >additional mechanical properties in terms of fracture >toughness, elongation at break, ductile to brittle >transition, etc. Does anyone know if the ASME books contain >mechanical properties beyond the typical yield, ultimate >strengths and elongation? > >Thanks in advance!

rjleslie AISI 4140 is a medium carbon low alloy steel 1% Cr- 0.5 Mo which can be heat treated to improve toughness, elongation and R.A properties. This can be heat treated to get definitely improved toughness by resorting to double tempering. You have to specify the fracture toughness and mech properties improvements you would desire from your specific need. You will not get readily any tailor made list from standards / code data with fracture toughness variations, elongation & R.A. You will get some research papers publications on studies done to improve toughness / elongation R.A. To me it appears that you are not clear what you want to get from AISI 4140 steel for improved toughness . elongation and R.A. Simply asking more in-depth information from published standards may not help you. Suggest that you go through research publications on 4140 grade material with improved toughness by heat treatment variations (viz., double tempering) and apply the same for your need Hope this helps C.V.Srinivasan Nishi Engineers Pvt Ltd India E-mail: nishi@vsnl.com August 10, 2010 >SA 372 is currently specified (%7E ASTM A 372 or similar to >SAE 4140) and are interested in fracture toughness, >elongation at break, and reduction in area properties. We >have a lot of variables in the application that need to be >better defined as we were searching for a more in-depth >availability of the mechanical properties.