Most of the existing rapid prototyping processes are still quite expensive and many of them generate substances such as smoke, dust, hazardous chemicals, etc., which are harmful to human health and the environment. Dr. Ming Leu of the University of Missouri-Rolla, Virtual & Rapid Prototyping Lab. is developing a rapid prototyping process that uses cheap and clean materials and can achieve good layer binding strength, fine build resolution, and fast build speed. They have invented such a process, called Rapid Freeze Prototyping (RFP), that can make three-dimensional ice parts of arbitrary geometry layer-by-layer by freezing of water droplets.

1. Presentation on
Rapid Freeze Prototyping
Submitted by –
Sandeep Kashyap
M.Tech. (Prod.
Engg.)
2015PR21
Submitted to –
Dr. Praveen Kumar
Agarwal
Mechanical Engg. Deptt.
MNNIT Allahabad

2. Overview
 Rapid Freeze Prototyping
 Introduction
 Process
 Potential Applications
 Advantages and Disadvantages

3. RAPID FREEZE
PROTOTYPING

4. Introduction :
 Most of the existing rapid prototyping processes are still quite
expensive and many of them generate substances such as
smoke, dust, hazardous chemicals, etc., which are harmful to
human health and the environment.
 Dr. Ming Leu of the University of Missouri-Rolla, Virtual &
Rapid Prototyping Lab. is developing a rapid prototyping
process that uses cheap and clean materials and can achieve
good layer binding strength, fine build resolution, and fast
build speed.
 They have invented such a process, called Rapid Freeze
Prototyping (RFP), that can make three-dimensional ice parts
of arbitrary geometry layer-by-layer by freezing of water
droplets.

5. Process :
 As shown in Figure 1, water is pumped from a reservoir to the
nozzle by a pump and then deposited onto the previous
solidified ice surface or the substrate.
 The newly deposited material is cooled by both the low
temperature environment and the ice surface.

6.  As a result the deposited water freezes rapidly and sticks to the
previous layer, forming a new layer of the part. Where
necessary, brine is used instead of water to build the support.
 The nozzle and the transmission pipe are heated and kept at a
temperature just above the freezing point of water so that the
material may flow smoothly.

7. Potential Applications :
(1) Part Visualization : Parts can be built for the purpose of
visualization. Example can be seen in Figures 3.

8. (2) Ice Sculpture Fabrication : One application of rapid freeze
prototyping is making ice sculptures for entertainment purposes,
while Figure 5 shows the part made by RFP.

9. (3) Silicon Molding : The experiments on silicone molding have
shown that it is feasible to make silicone molds with ice patterns
(see Figures 6). The key advantage of using ice patterns instead
of plastic or wax patterns is that ice patterns are easier to remove
(without pattern expansion).

10. (4) Investment Casting :For making patterns for the investment
casting. Figure 7 shows a metal model made by investment
casting using ice patterns from RFP.

11. Advantages and
Disadvantages :
RFP has the following advantages:
(1) Low running cost : Rapid Freeze Prototyping (RFP) process is
cheaper and cleaner than all the other rapid prototyping
processes. The energy utilization of RFP is low compared with
other rapid prototyping processes such as laser stereolithography
or selective laser sintering.
(2) Good accuracy : RFP can build accurate ice parts with
excellent surface finish. It is easy to remove the RFP made ice
part in a mold making process, by simply heating the mold to melt
the ice part.

12. (3) Good building speed : The build speed of RFP can be
significantly faster than other rapid prototyping processes,
because a part can be built by first depositing water droplets to
generate the part boundary and then filling in the enclosed
interior with a water stream (see Figure 8). This is possible
due to the low viscosity of water. It is easy to build colour and
transparent parts with the RFP process.

13. On the other hand, RFP has also the following disadvantages:
(1) Requires a cold environment : The prototype of RFP is made
of ice and hence it cannot maintain its original shape and form in
room temperature.
(2) Need additional processing : The prototype made with RFP
cannot be used directly but have to be subsequently cast into a
mold and so on and this increases the production cost and time.
(3) Repeatability : Due to the nature of water, the part built in one
run may differ from the next one.

14. References :
 Chua C.K., Leong K.F. and Lim C.S., Rapid Prototyping:
Principles and Applications 2nd Edition, World Scientific
Publishing Co. Pte. Ltd., Singapore, 2003
 Wei Zhang, Ming C. Leu, Zhimming Ji, Yongnian Yan. Rapid
Freezing Prototyping with Water. (a)Department of Mechanical
Engineering, New Jersey Institute of Technology, MEC 204, 200
Central Ave., Newark, NJ 07102, USA (b)Department of
Mechanical Engineering, Tsinghua University, Beijing 100084,
China